At the Mount Union hospital, a 5-year old white male child in good general health and physical condition was presented at the Saturday walk-in clinic by his mother. He was brought in because he had a fever, was cranky and had complained of a sore throat for about 24 hours. On physical examination by the attending resident, the patient had a fever of 39.3C, and he had considerable swelling and drainage of the pharynx and in the conjunctivae. His tonsils were enlarged and coated with a white patchy exudate. He had a red throat and swollen anterior cervical lymph nodes. His ears were clear. His chest sounded clear and he had no additional remarkable findings on routine examination.
Disease: Streptococcal Pharyngitis (Strep Throat)
Cause: Streptococcus pyogenes (white exudate = bacterial infection)
Diagnosis: Rapid strep test
Transmission/Portal of Entry: Upper respiratory tract via respiratory droplets
Treatment: antibiotics
Prevention: good hygiene, infectious individuals stay home for 2 days after treatment
Complications: Scarlet Fever, Rheumatic Fever
Susceptibility: Children
A lethargic 22-month old black female was presented by her mother to the emergency room at 2:15am on a Sunday. The child had a history of a runny nose, hoarse cough and low-grade fever (~99F) for the past 48 hours. The mother was concerned about the forced and noisy breathing of the child. The pediatrician examined the child and found cloudy eyes and mild inflammation of the ears, but no overt signs of bacterial infection (no significant changes in the eardrums). The throat of the child was red and coated with mucus. The larynx was swollen and raw. The physician performed a rapid Strep test and found it was negative. Throat swabs were taken for culture. The physician placed the child in a room with a warm vaporizer for about 30 minutes. This dramatically improved the breathing of the child.
Diagnosis: Croup = An upper airway infection that blocks breathing and has a distinctive barking cough; may begin like a cold, progress into barking cough due to swelling of vocal cords
Cause: parainfluenza virus
Transmission: Respiratory droplets
Treatment: supportive care, steroids
Prevention: good hygiene, avoiding contact with infected
Susceptibility: generally occurs in children
A 22-year old male college student was presented at the ESU health clinic. He looked tired and pale. He presented because of high fever and chest pain. He was afraid he was having a heart attack (bad week of exams). He was examined immediately by the PA and an EKG strip was run. He had no evidence of acute heart problems. The attending physician visited the patient. He obtained the following history from the past 36 hours. The patient had a tight cough. He had significant muscle aches and pains. He had a bad headache and had had fevers of 101-103F.
The physician ordered a chest x-ray. It did not show any significant consolidated inflammation suggestive of pneumonia. The patient showed significant nasal drainage and a moderately tight, but productive cough on physical exam. He had a fever of 101F and generally inflamed mucous membranes. A rapid Strep test showed no evidence of Streptococcal infection and his tonsils and adenoids had been removed.
Diagnosis: Influenza
Cause: Influenza virus types A and B
- Enveloped RNA virus
- Hemagglutinin and neuraminidase mutations produce the ever changing array of strains
- Mutations occur via antigenic shift and drift
Transmission: via inhalation of airborne viruses or self-inoculations
Prevention: good hygiene, vaccine
Treatment: antiviral drugs in first 48 hours and shorten duration; supportive care for symptoms
Complications: Bacterial pneumonia – occur most often in elderly, children, and those with chronic disease
A 68-year old patient with Alzheimer disease was brought to the emergency room by the staff of a local nursing home. He presented as lethargic with a sallow complexion. He had an admission temperature of 102.4F and a respiratory rate of 33/minute. During respiration, the right side of his chest moved better than the left. He showed dense consolidation of the lower lobe of the left lung on physical exam. A sputum sample revealed blood and a greenish color.
A chest x-ray showed tight consolidation of the left lung with evidence of formation of cavities in the lung tissue from cytotoxic damage. The patient complained of chills in the exam room, combined with his fever. A smear of his sputum demonstrated no acid-fast bacteria.
Diagnosis: Klebsiella Pneumonia (leading cause of nosocomial death)
- Gram stain would reveal gram negative, rod shaped, with capsule
- TB ruled out because it is not acid-fast bacteria
- green sputum indicates bacterial infection
Cause: Klebsiella pneumoniae
Transmission/Portal of entry: inhalation
Treatment: antibiotic therapy and supportive care
Prevention: hygiene and ascriptive techniques by health care workers
Susceptibility: AIDS patients, very young, very old, people living in nursing homes, jails, hospitals
A 35-year old accountant presented to his physician with a steady burning pain just right of the mid-line of the abdominal region in an area from 1 to 4 inches above the “belly button.” The pain usually followed meals by about 1-3 hours. He had several episodes of vomiting, which included frank blood.
On physical examination, the patient had no fever. He appeared generally well. He had no evidence of weight loss. He showed slight rebound tenderness in the upper abdomen. An occult blood test revealed the presence of blood.
Diagnosis: Peptic Ulcers
Cause: Helicobacter pylori
- blood in vomit indicates bleeding ulcer (upper respiratory)
Transmission: Fecal-oral
Susceptibility: those colonized by H. pylori
Treatment: antimicrobial and acid blocking drugs
Prevention: lifestyle changes
A 4-year old girl presents at the emergency room with bloody diarrhea, fever and vomiting. The child’s mother reports that the child has had these symptoms for about 24 hours and she has not passed any urine for about 12 hours.
The child is enrolled in a day care center and the group had recently made a field trip to a fast food place to learn about different jobs. The children had a lunch of ground beef, fries and cola after meeting with different workers. This field trip was 4 days earlier on Friday. The child had a temperature of 39C and showed physical signs of dehydration. Blood samples drawn showed evidence of greatly reduced kidney function and lysed red blood cells.
Diagnosis: Escherichia coli 0157:H7
- Gastroenteritis
- leading cause of food borne illness
- has powerful toxin that can cause sever illness
- Shiga toxin causes lyse red blood cell
Susceptibility: children under 5 years of age and elderly, the infections can cause hemolytic uremic syndrome
Treatment: no antibiotics, rehydration, dialysis
Complications: kidney failure, hemolytic uremic syndrome
Prevention: proper food handling and preparation
A 26-year old white female presents in her physician’s office with genital itching and sharp, severe pain on the labia. She complains of three previous episodes of pain over the past 6 months, each of which were followed by the appearance of red sores which crusted and healed without a scar.
On examination the physician observes a cluster of small red blisters localized in the area of the worst pain. No significant discharge was observed from the vagina. The patient’s urine was clear and yellow. Urinalysis revealed normal specific gravity, no sugar, no protein, no white blood cells or red blood cells and no bacteria. The patient’s temperature was 36.5C.
The patient history reveals that she is unmarried. She is moderately sexually active and currently using an oral contraceptive which she has been taking for about 4 years. The woman stated that she has had 5 sexual partners over the past year. She reported that her episodes have become progressively more severe.
Diagnosis: Genital Herpes
- reoccurring, latent
- viral
- characteristic lesions around genitals or rectum
Cause: Herpes simplex viruses type 2 (main cause) and type 1
Treatment: antiviral medicine, acyclovir
Prevention: abstinence, condom use, monogamy
Complications: other STDs, cervical cancer
A 22-year old woman presents at the walk-in health clinic with slight fever (38.5C), a complaint of frequent urination, burning on urination, vaginal discharge and a small lesion on the labia.
The woman reported that she was moderately sexually active and had three sexual partners in the past six months. Her last sexual contacts were about 7 days earlier. She had developed mild symptoms about 5 days earlier, beginning with a discharge from the vagina. She began having pain on urination about 3 days earlier.
Urine analysis revealed a pH of 8.2, some white cells and a few red blood cells. There was protein in the urine. A smear of the vaginal secretion showed a number of Gram-negative cocci.
Diagnosis: Gonorrhea
- bacterial disease
- female: painful urination
Cause: Neisseria gonorrhoeae
Transmission/portal of entry: mucous membranes of genitalia
Susceptibility: sexually active individuals
Treatment: antibiotics
Prevention: monogamy, abstinence, condom use
Complications: Pelvic Inflammatory disease (PID) – includes inflammation of other parts of the upper reproductive tract; buildup of scar tissue from PID can block fallopian tubes, causing sterility or ectopic pregnancies
A white male, 17 years of age presented at the emergency room with a severe headache, vomiting, and a stiff neck with pain running up his back. On admission, his temperature was 101F. The young man appeared to have trouble hearing during the nurse’s interview and also seemed to have trouble concentrating.
The history revealed that the young man is a wrestler for the local high school team. He had felt as though he were getting a cold the past few days, since his last meet in Hicksville. He did not smoke or drink, but he had attended a party two days earlier thrown by his girlfriend and the other cheerleaders to celebrate his victory in the sectionals. He had been holding his weight at 162 for the season, so he ate little and did not drink on the day of meets (today is a day of the meet).
On physical exam, the physician noticed several areas of small purplish spots on the skin of the back, thigh and arm. The boy thought those were from wrestling.
Diagnosis: Meningococcal meningitis
- sudden onset of disease
- petechiae
Cause: Neisseria meningitidis - gram negative, encapsulated diplococcus, normal microbiota
Transmission: inhaled in airborne droplets, attach to mucous membranes and multiply – travels through bloodstream to reach meninges
Treatment: antibiotics
Prevention: prophylactic antibiotic therapy
Complications: low BP, endotoxic shock, death
A missionary couple, living in West Africa, bring their 4-year old son to the office of their physician on the second day of a visit home to Minnesota. The boy had a mild episode of diarrhea about seven days earlier and would not eat. He seemed to recover, but the mother noticed that the boy was having trouble walking the previous night and had seemed to have trouble dressing himself and walking that day.
On examination, the patient had no significant fever (98.9) and normal bowel sounds. His chest, ears and eyes were clear. He had no rebound tenderness in the abdomen. The physician noted that the child had poor muscular reflexes in his arms and legs. The child also was a bit lethargic and seemed confused.
The family lives in an isolated village in Africa. The mother opposes vaccinations on personal grounds, so the child has only had the initial series of DPT shots and no other typical vaccines. The village where they live has many problems with parasites and insect borne fevers (including Dengue).
Urine, stool and blood samples were collected for analysis.
Diagnosis: Poliomyelitis
- blood samples would show antibodies
Cause: Poliovirus
Transmission: fecal-oral, contaminated water
Prevention: vaccination, OPV and IPV
Treatment: supportive care, physical therapy
Complications: Paralysis of the muscles of the legs, abdomen, back, intercostals, diaphragm, pectoral girdle, and bladder can result. Loss of control of cardiorespiratory regulatory centers; requires use of mechanical respirators (Bulbar Poliomyelitis)
A 24-year old, female graduate student in biology presented with exhaustion, weakness and a low grade fever. She was pale and showed poor ability to concentrate.
Her history revealed that she had gradually become increasingly tired and weakened over the past two months. She had experienced low-grade fevers over the past month and felt she would need to drop out of her graduate program if she did not get this under control. She had had a severe strep throat about a year earlier and showed some signs of rheumatic fever at the time. She had had minor dental surgery about two months earlier.
On examination, she had a temperature of 100F. She had slightly enlarged cervical lymph nodes. She had a heart murmur, with abnormal valve sounds. Her ears, eyes and throat were clear. She had clear lungs and there were no significant findings in other systems.
Diagnosis: Subacute Endocarditis
- almost always preceded by some form of damage to the heart valves or by congenital malformation
- irregularities in valves encourage attachment of bacteria
Cause: a. Streptococcus pyogenes caused the problem most commonly caused by bacteria of low pathogenicity, often ordination in oral cavity - Alpha-hemolytic streptococci such as Streptococcus sanguis, S. oralis, or S. mutans
Transmission: minor disruptions of skin or mucous membranes introduce bacteria into bloodstream
Susceptibility: people who have suffered rheumatic fever and the accompany damage to heart valves
Prevention: prophylactic antibiotic therapy before dental procedure/surgical procedure
Complications: sepsis, heart problems, death, stroke, aneurysm
Treatment: antibiotics
A 35-year old Native-American male presents in the clinic with a complaint of recurrent low-grade fevers, sweating, weakness, muscle pains and a loss of about 10% of his body weight over a 4 month period. The worsening weakness and muscle pain prompted the visit.
The patient reports that he has been working on a bison slaughter line owned by his tribe, and blood and tissue juices often splash in his face or contaminate minor hand and arm injuries. He likes to hunt and fish. He is married and has two children. He eats fairly well, but he has not been as hungry lately. He had rheumatic fever as a child and was in a fairly serious car accident three years earlier, resulting in a leg broken in three places. He feels he was physically fit prior to the past 4 months. He likes to play basketball and softball. He has had all the usual childhood immunizations, but does not see the doctor often.
On physical examination, the patient has a temperature of 101F. He has mildly swollen lymph nodes in the neck and under the arms. He has blood pressure of 136/86, and a normal heart rate without a heart murmur. There is no evidence of acute respiratory or gastrointestinal infection.
Diagnosis: Brucellosis
- fever, sweats, muscle pain, recurrent fevers,
Transmission: eating or drinking unpasteurized/raw dairy products, products from infected animals, bacteria can enter wounds in the skin/mucous membranes through contact with infected animals
Susceptibility: slaughterhouse workers, meat packing employees, veterinarians, people with skin wounds, hunters, etc.
Prevention: using gloves, goggles, and gowns, avoiding unpasteurized dairy products
Treatment: antibiotics
A woman is brought to the emergency department where you are working triage. She has an extremely swollen right lower leg. You see what appears to be an old surgical wound in the mid-calf, with rough scar tissue surrounded by purplish red skin. She is in a lot of pain and her husband speaks for her. He tells you that three weeks ago she had a group of moles removed form that area. It had appeared to heal initially, but three days ago the incision areas started looking bigger rather than smaller. She did no return to the physician, hoping the condition would resolve itself. In the past three days, the areas has begun to swell and become very hot. You call the attending physician immediately because you know that this is a serious condition. The patient is sent straight to surgery where the wound is de-brided. Gram positive cocci growing in chains are recovered from the wound. She is transferred to intensive care and put on high-dose intravenous antibiotics for the next 18 hours, but the next evening her leg is amputated below the knee. She remains in the hospital for two months following surgery, and requires long-term antibiotic therapy and multiple skin grafts on her upper leg.
Diagnosis: Necrotizing Fasciitis
- nonspecific flu-like symptoms at first
Cause: Streptococcus pyogenes
Treatment: antibiotics such as penicillin
Prevention: proper wound care
Complications: amputation, death
You are an emergency medical technician and are called to the home of Kevin, a 13 week old boy who has become listless and is having trouble breathing. The parents report that Kevin used to smile, but lately he has not smiled, nor has he had any other noticeable facial expressions in the last two days. Kevin’s eyes are open when you arrive, but he does not seem to refocusing. You place your outstretched finger under his fingers and he fails to grasp it. You life his foot and it drops back to the mattress. The parents report that he has not had a bowel movement in 3-4 days.
Diagnosis: Food botulism
- progressive paralysis of all voluntary muscles (canning)
Cause: Clostridium botulinum (different toxins produce neurotoxins)
Treatment: washing of intestinal tract, administration of botulism immune globulin, treatment with antimicrobials
Prevention: destroying endospreos in contaminated food through proper canning techniques for food born cases
Transmission: vehicle (food borne toxin, airborne organism)
Complications: Paralysis
In December, a 19 year old college student experiences a severe headache, nausea, vomiting, and fever. The student suspects a case of the flu and geese to the health care for diagnosis. By the time he arrives, he is feeling worse with stiff neck and disorientation. The doctor immediately prepared to perform a spinal tap.
Diagnosis: Pneumococcal Meningitis
- begins like mild cold, followed by sudden onset of severe throbbing headache, fever, pain and stiffness of neck and back, nausea, vomiting
- deafness, confusion, loss of consciousness, coma, deaths
- damage mostly from inflammatory response
Cause: Streptococcus pneumoniae (G+)
Transmission: droplet contact
Prevention: two vaccines – PCV 13 and PPSV23
Treatment: antibiotics
An 18 year old college freshman reports to the campus health care clinic. He states that he has felt very fatigued and generally ill for about a week, and developed a sore throat, fever, and headache the day before. He has been sleeping more than usually and has virtually no appetite. He says his girlfriend, who attends college in a different state and whom he saw last month, has also been feeling very fatigued for the last two weeks or so, but displays none of the student’s other symptoms.
Diagnosis: Mononucleosis infection
- signs and symptoms appear after 30-50 day incubation
- sore throat, fever, exudate in throat, enlarged spleen and liver, leukocytosis, fatigue is hallmark of disease
Cause: EPV (Epstein Barr Virus) – herpes family
Treatment: supportive
Transmission: direct oral contact and contamination with saliva
Prevention: avoid direct contact with infected (kissing disease)
The patient was a 40 year old male admitted for chronic cough and a 2 month history of intermittent afternoon fever. He denied both a history of traveling and contact with animals over the previous three months. Associated symptoms included general malaise, anorexia, and the loss of 6 kg body weight within the previous 2 months. On admission, the vital signs were shown as blood pressure: 124/68 mmHg; pulse rate: 80/min; respiratory rate: 22/min; body temperature: 38.5 C. Physical examination revealed a pan-systolic murmur over the apex and left lower sternal border. An abscess in a molar cavity that required debridement was found, although the patient had not complained of dental pain. Lab tests revealed anemia with a hemoglobin level of 10.4 g/dL
Diagnosis: Subacute endocarditis
- Janeway lesions, Osler’s nodes, enlarge spleen , irregularities in valves encourage attachment of bacteria and provide entrance into bloodstream
- almost always proceeded by some form of damage to heart valves or by congenital malformation
Cause: bacteria of low pathogenicity, often originating in oral cavity; Alpha-hemolytic streptococci such as S. sanguis, S. oralis, S. mutans
Prevention: prophylactic antibiotic therapy in advances of surgical or dental procedures
Transmission: minor disruptions of skin or mucous membranes introduce bacteria into the bloodstream and lead to colonization; brushing teeth too hard, dental procedures, minor cuts, prosthetic valves
Treatment:
A 26 year old man reports to his physician in late October, complaining of a sudden onset of fever, dry cough, headache, and body aches. The man states he received his flu shots ten days prior and myst have gotten the flu from the immunization. He also states that he had just returned two days before from a weeklong trip to Hong Kong. He mentions that a highlight of his trip was a visit to the farmer’s market filled with fresh produce and livestock. A culture confirms the patient is infected with…
Diagnosis: Influenza
- sudden fever, pharyngitis, congestion, cough
- symptoms produced by immune response to virus
Cause: Influenza virus types A and B
Transmission: via inhalation of airborne droplets or by self-inoculation
Treatment: antiviral drugs within 48 hours, supportive care for relief
Prevention: immunization
In September 1998, a 36 year old male soldier in the French Foreign Legion with hemoptysis (coughing up blood) was sent back to France from Djibouti. He expectorated bloody sputum after running and on a few other occasions. His medical history was not unusual. When the patient was hospitalized, 2 weeks after the initial symptoms, he began to experience progressive fatigue. He did not experience fever, weight loss, night sweats, anorexia, cough, dyspnea, or chest pain, and did not produce sputum. Results of the clinical examination were normal. The chest X-ray showed a triangular consolidation of the left upper lobe with blurred limits and small cavitary lesions.
Diagnosis: Tuberculosis
- initial symptoms include minor cough and mild fever
- later symptoms include difficulty breathing, chest pain, wheezing, and coughing up blood
Cause: Mycobacterium tuberculosis
Transmission: via droplets of respiratory mucus suspended in air
Prevention: limiting exposure to infectious airborne particles, patient isolation, live attenuated vaccine BCG (not in U.S.)
Treatment: antibiotics
About 5 days ago, a 45-year-old patient began experiencing symptoms of what appeared to be a simple upper respiratory tract infection. She has come to the ER after experiencing mild paralysis in her arms and an abnormal heartbeat. While in triage, she suddenly develops difficulty breathing and is sent up to the respiratory unit where you are the charge nurse. In your initial assessment, you discover gross inflammation of her pharynx and tonsils, and the entire area appears to be covered by a grayish-white colored membrane. You order a throat swab and additional specimens for microbial analysis, and you immediately send the patient into isolation.
Cause: Cornybacterium diphtheriae
Virulence factor: Diphtheria toxin prevents polypeptide synthesis and causes cell death and is coded by lysogenic phage
Portal of entry: Spread person to person via respiratory droplets or skin contact
Signs/Symptoms: Sore throat, oozing fluid that hardens into a pseudomembrane that can obstruct airways
Psuedomembrane can cover the respiratory passages, resulting in death by suffocation
Susceptibility: Immunocompromised or nonimmune individuals develop symptomatic infections
Treatment: Administration of antitoxin and antibiotics
Prevention: Immunization
A 58-year old lawyer presents in the emergency room with a headache, irritability, generalized muscle pain and uncontrollable back spasms. He has back spasms that became extremely painful. He is on medication for high blood pressure (beta blocker) and has mild asthma. He injured himself about 10 days earlier, puncturing his left arm with a nail from an old barn he is tearing. The wound has produced moderate quantities of pus, but he has been keeping it clean. The wound was sampled for microscopic examination and culture, and the results indicate gram-positive anaerobic, bacilli. The back appears to have very tight contractions and spasms.
1) What is your diagnosis here? Teatnus
2) What is the scientific name of the organism? Clostridium tetani
3) what is the common name for the disease? lockjaw
3) What is the proper treatment of this problem? Tetanus immune globin (TIG), debridement, and Td vaccine Muscle relaxer for muscle spasms along with antibiotics
4) How could this have been prevented? Tetanus toxoid with booster every 10 years
A 62-year old diabetic black man presents in the emergency room with a swollen left leg with areas of blanching and blue mottling. A “foul odor” is coming from a dressed wound. The physicians remove the dressing and a brownish fluid is seeping from a wounded area. The fluid contains what appear to be small bits of the tissue. No pus appears to be present. The wound has a strong “rotten” odor. Five days earlier, while at his work as a farmer, he caught the leg in his manure spreader, sustaining a deep, crushing, grossly dirty injury. His wife cleaned the wound as well as she could with soap and water, dressed it with clean gauze, and wrapped it tightly with an elastic bandage to stop the bleeding. The second day they redressed the wound and applied triple antibiotic ointment. The patient treated his pain with ibuprofen (Advil). He reported the pain was not very bad for the first 72 hours. In the past 24 hours, the leg swelled and the mottling began to appear. A foul odor and severe pain accompanied the swelling.
1) What is your diagnosis in this case?
Gas gangrene
2) name the etiological agent.
clostridium perfringens
3) how would this microorganism be cultured in the lab?
anaerobic and a controlled environment
4) How should this wound be treated?
Remove dead and infected tissue, amputation may be necessary, antibiotics for treatment- IV antibiotics to control toxins
5) What is the significance of his diabetes, if any?
Blood supply inadequate to wound/throughout the body because of poor blood circulation to the womb.
A 27-year old white female presented at the walking clinic of her local physician on August 15. On physical exam, the patient had a fever of 38.5C. She appeared fatigued, had tender joints, and complained of a headache, a stiff neck and a backache. The physician noticed a circular “rash” about 5 inches in diameter, with a bright red leading edge and a dim center in the form of a “bull’s eye”. The physician noted an irregular heart beat. The patient complained of lack of ability to concentrate.
The patient gave the following history: She is a graduate student in the wildlife program at the university in town. She was in the field for three weeks in Wisconsin during the months of May and June. She tracks small mammals in the field and studies their behavior. It had been a warm, wet spring and she complained of a large number of biting flies, mosquitoes and ticks in the area. She felt well until about 2 weeks after returning to her home. Since that time, many of her symptoms had progressed. She finally found that she could take it no more.
What is your best diagnosis of this case?
What features are critical to your diagnosis?
What further steps should be taken to clear up the problem?
Lyme Disease
Working in the Wisconsin woods, the bull’s eye rash, fever, cardiac changes, joint pain
Antibiotic therapy with Ampicillin and ceftriaxone or erythromycin, monitor for long-term cardiac and joint problems and treat symptomatically.
A 24-year old female automotive technician presents herself at the doctor’s office. She complains of fever and of pain in her left hand.
On physical examination, the patient had a deep wound on her left palm that was oozing pus. She had purplish, red streaks running up her left arm. She had enlarged lymph nodes at the elbow and under her arm. The patient’s skin was warm and dry.
In her history, the patient had punctured her left palm with sharp metal from the undercarriage of a “real cherry” 1977 Malibu about a week earlier. She said the wound had bled for a few minutes and she thought that she had washed it “real good” with soap and water. She had covered the wound with a large “band-aid” and gone back to work. She developed a fever about three days later. For the past couple of days, she “did not feel so good” and had vomiting and diarrhea.
What type of infection do you believe she has in this hand?
Staphylococcus aureus
From complaint and physical examination, which of the symptoms lead you to your choice of agent?
the fever, wound with oozing pus and enlarged lymph nodes
From the history, which of the information confirmed your choice?
She had diarrhea and vomiting.
Which of the following is most likely to follow this infection?
toxic shock syndrome
A suspicious envelope arrived for sorting at rural post office. The envelope was opened and found to contain white powder. Approximately two days later, the postal worker who handled the letter developed cutaneous boils, which were and 1 to 5 cm in diameter with central necrosis and eschars. He and his wife also developed a mild nonproductive cough with fatigue, myalgia for 72 hours, followed by severe dyspnea, diaphoresis and cyanosis.
A- Bacillus anthracis
A 66-year-old man incurs extensive thermal burns to his skin and undergoes skin grafting procedures in the surgical intensive care unit. Two weeks later, he has increasing respiratory distress. Laboratory studies show hemoglobin of 13.1 g/dL, hematocrit 39.2%, platelet count 222,200/mm3, and WBC count 4520/mm3 with 15% monocytes. A chest radiograph shows extensive bilateral infiltrates with patchy areas of consolidation
Pseudomonas aeruginosa
A 45-year-old male became ill approximately 2 to 3 weeks ago following an alcoholic spree. He had nausea, vomiting, dehydration, confusion and high fever. He died suddenly shortly after admission
Gram stain of sputum obtained before death shows Gram positive cocci in pairs. The right lung was heavy weighing 700 grams. Its lower lobe showed diffuse gray consolidation. The trachea and bronchi contained a great deal of mucus, and the mucosa was dark red.
Streptococcus Pneumoniae
A 4-year-old female had a gradual onset of fever, productive cough, anorexia and diarrhea about eleven days prior to death. The breath sounds were harsh, and a few cracking rales were heard over the right base posteriorly.
Sputum smear showed acid fast bacilli. Sputum cultures results became available four weeks after death, showing the presence of slow-growing colonies. The lungs showed fibrinous exudates over the pleural surfaces.
Mycobacterium tuberculosis
A 25-year-old man is involved in an accident in which he is ejected from the vehicle. He sustains a compound fracture of the left humerus and undergoes open reduction with internal fixation of the humeral fracture. Several days later, he has marked swelling of the left arm and crepitus Crackling, bubbling sound)
On the arms, there is marked swelling and tissue destruction with black discoloration. Boxcar shaped gram positive rods are seen in the gangrenous tissue. The organism requires anaerobic culture conditions and egg yolk agar for growth
Clostridium perfringens
A 45-year-old woman is being treated in the hospital for pneumonia complicated by septicemia. She has required multiple antibiotics and was intubated and mechanically ventilated earlier in the course. On day 20 of hospitalization, she has abdominal distention
Clostridium difficile – due to the exotoxin
A 15-year-old boy presents at the emergency room with a 24-hour history of painful urination. He has discharge in his underwear and on the tip of his penis. Urine appears clear, although many white blood cells are present.
B- Neisseria gonorrheoae
A female patient presents to the emergency room with a history of cramping, abdominal pain over the previous 3 days, and vaginal bleeding. She gives no history of urinary tract infection, discharge, chills, fever, or vomiting. The pain has increased over the previous 24 hours, and she is now experiencing a pain in her right side. On examination she has a fever and pelvic pain. An endocervical swab was taken and the sample used to perform the ligase chain reaction, which amplifies nucleotide sequences present on the multicopy plasmid present in each cell of the obligatory intracellular bacteria producing the infection.
A- Neisseria gonorrhoeae and Chlamydia trachomatis.
A 62-year-old woman with a previous history of gastric ulcers presents to her gastrointestinal clinic. Recently she has noticed increasing episodes of heartburn with pressure in the abdomen which radiates to her chest and neck. Radiology shows a thickened fold within the stomach. A biopsy of the antral stomach (obtained by gastroscopy) shows moderate gastritis.
A- Helicobacter pylori
A college student presents to the outpatient medical clinic for evaluation of diarrhea and abdominal discomfort. His symptoms began 1 week ago, and he has subsequently had up to three loose bowel movements a day, plus crampy abdominal pain. The patient states that he has “not been able to hold anything down” during this time except some fluids. The last meal he ate, prior to infection, was at a fraternity cookout where he had chicken.
B- Campylobacter jejuni
A 9-year-old boy with a 2-day history of diarrhea presents to the emergency room with blood in his stools and increased stool volume. He has vomited once. The boy went to a cookout 5 days earlier and ate a hamburger that was still “pink” inside.
C- Enterohemorragic E-coli
An 8-year old boy falls while playing and abrades the skin over his thigh and rib. The injury does not appear serious and no effort is made to clean the wound or apply antibiotic creams. The wound of the hip worsens after 3 days with inflammation and small amount of purulence. That evening the child develop a high fever ,40 C (105 F), headache and a diffuse rash. By the time the child arrives to the hospital he is hypotensive complains of severe myalgia and has diarrhea. After one more day his skin desquamates (including his palms and soles) and he develops renal and hepatic abnormalities.
E- Toxic shock syndrome toxin-1
A seven -year old girl sees her pediatrician for a cutaneous pustule on her arm the site where her kitten had scratched her 1 week prior to the appointment, Her mother has also noticed an enlargement of the right axillary lymph nodes. The girl has low grade fever and complains that she is tired. The pediatricians collect cultures of the pustule, lymph nodes and blood. But all the results are negative after 1 week. Which organisms is most likely for this infection?
A- Bartonella Hanselae (cat disease)
Over a period of three weeks, a total of five newborns in the hospital nursery developed staphylococcal infections with S.aureus bacterimia . The isolates had the same colony morphology and hemolytic properties and identical antimicrobial susceptibility patterns, suggesting that they were the same. Later molecular methods showed the isolates were identical. Which of the following should be done now?
E- Culture using mannitol salt agar of the anterior nostrils of the physicians nurses and others who cared for the infected babies
An 80-year-old female is transferred from a nursing home to the hospital because she is suspected of having pneumonia. She is experiencing chest pain, chills, fever, and shortness of breath. She has a productive cough (meaning that she is coughing up sputum). A Gram-stain of the sputum reveals numerous white blood cells and numerous Gram-positive diplococci. Upon receipt of the Gram-stain report, the physician treats the patient for a pneumonia caused by ___.
d. Streptococcus pneumoniae
A 20-year-old male is admitted to the hospital with fever, headache, stiff neck, sore throat, and vomiting. The attending physician suspects that the patient has meningitis and immediately performs a lumbar puncture. A cerebrospinal fluid (CSF) specimen is rushed to the laboratory, where it is processed immediately. After centrifuging an aliquot of the specimen, the sediment is spread onto a microscope slide, fixed, and Gram-stained.
Neisseria meningitidis
A 16-year-old female is admitted to the hospital with severe abdominal cramps and bloody diarrhea. She has a fever of 102oF. She has been experiencing her symptoms for the past three days, since several hours after eating at a fast food restaurant with a group of her friends. She recalls that the hamburger she ate was not very well cooked. (It is later learned that the meat being used in that restaurant to prepare hamburgers has been recalled due to bacterial contamination.) All of the following organisms can cause diarrhea, but which is the most likely cause of her illness?
c. Escherichia coli O157:H7
A three-year-old developed a series of blister like lesions around her nose and mouth. The lesions remained localized to the area and began to scab over the next couple of days. However the parents grew concerned when the second child developed the same kind of lesions
Numerous gram-positive cocci in chain and numerous pus cells culture shows large number of group A beta hemolytic streptococci and a few Staph aureus What is the most likely diagnosis of the disease?
Impetigo
Your patient has a subacute bacterial endocarditis caused by a number of the viridians group of Streptococci. Which one of the following sites is MOST likely to be the source of the organism?
A- Skin
A 19-year-old female visits the clinic complaining of a frequent, urgent desire to urinate, a burning sensation during urination, and pain above her pubic bone. The physician suspects cystitis and arranges for the patient to collect a clean-catch, mid-stream urine specimen. The urine is cloudy and tinged with blood. In the laboratory, a colony count confirms that the patient does have a urinary tract infection. The pathogen causing the infection is producing pink colonies on MacConkey agar. Which one of the following pathogens do you suspect is causing this patient’s cystitis?
b. Escherichia coli
A 2-year-old girl is admitted to the hospital with massive tissue destruction along her right arm. The skin is a violet color and large fluid-filled blisters are present. The patient has a fever, a rapid heart rate, low blood pressure, and seems confused. Her mother informs the physician that the child had been recovering from chickenpox, and, for the past two days, had frequently been scratching at chickenpox lesions on that area of her arm. Once the area appeared to have become infected, the infection spread very rapidly. A Gram-stain of exudate from the infected tissue reveals Gram-positive cocci in chains. The physician suspects that her infection is being caused by ___.
e. Streptococcus pyogenes (Group A strep)
A 10-year-old girl presents to her primary care physician with a severe sore throat, headache, nausea, and abdominal pain. Examination shows the back of her throat is covered in a purulent exudate with white pus-filled nodules. Culture of the exudate on blood agar produces beta-hemolytic colonies composed of gram-positive cocci in chains. (7 points) What organism do you suspect? Explain your reasoning. (3 points) What disease is this?
Streptococcus pyogenes & Streptococcal pharyngitis
A 67-year-old woman with non-insulin-dependent diabetes mellitus (NIDDM) presents with a 2-day history of wheezing and a productive cough. On physical examination, she has a rapid pulse and fever. A chest x-ray shows pulmonary infiltration classic of pneumonia. A Gram stain shows gram-positive cocci in pairs and short chains, which were alpha-hemolytic on blood agar and sensitive to Optochin. (7 points) What organism is the patient infected with? Explain your reasoning. (2 points) What two risk factors does she present for the disease? (2 points)
Streptococcus pneumoniae & Age & NIDDM
A 44-year-old woman was seen in the office for shortness of breath. She had previously been diagnosed with mitral regurgitation (backward blood flow through the mitral valve), but this problem has been stable. She had no symptoms until a few days earlier. Her physician did an echocardiogram that showed worsened mitral regurgitation and some 1 cm vegetations (small lumps often associated with valvular infection) on the anterior valve leaflet. Three sets of blood cultures showed gram-positive cocci in chains. She was reluctant to enter the hospital and asked if she could be treated with oral medications at home. (5 points) Optochin is used to rule out S. pneumoniae. (Spneumoniae doesn’t grow in the presence of Optochin) What organism is causing this woman’s disease? Explain your reasoning. (3 points)
Gram-positive cocci in chains suggests streptococci.
An 11-year-old girl is admitted to the hospital for treatment of lymphoma. During cytoreductive chemotherapy, she develops a fever and pneumonia. Analysis of pulmonary fluid shows a few white cells (neutrophils) and slender, gram-negative rods. The isolated bacteria produce a characteristic apple-green pigment on trypticase soy agar. (7 points) What organism is likely to be causing the infection? What led you to this diagnosis? (2 points)
P. Aeruginosa
A 5-month-old boy is admitted to the hospital with a 24-hour history of choking spells. These began with repeated coughing where the child turned red and gasped for breath. In the previous 2 days he had also had two episodes of vomiting. The baby was found to have an increased breathing rate, which was labored, but his chest x-ray showed no evidence of pneumonia. Blood work showed an abnormally large percentage of lymphocytes (70%). Nasopharyngeal swabs cultured grayish, “mercury-like” colonies, and a Gram stain revealed minute gram-negative coccobacilli. (5 points) What is wrong with the baby? What led you to this diagnosis? (3 points),
Whooping cough. Pertussis
A 9-year-old boy with a 2-day history of diarrhea presents to the emergency room with blood in his stools and increased stool volume. He has vomited once. The boy went to a cookout 5 day earlier and ate a hamburger that was still “pink” inside. On examination he is well, apart from some dehydration. A culture of stool samples produces lactose-positive (pink) colonies on MacConkey agar, but non-fermenting colonies on MacConkey with sorbitol substituted for lactose. (6 points) (amongst coliforms only E.coli can ferment sorbitol What is most likely wrong with this child?
Enterohemorrhagic E.coli
A male injection drug user presents at the emergency room with nausea, vomiting, and severe stomach cramps, which began suddenly 18 hours ago. When interviewed, the patient stated that his last meal was a carton of rice from a Chinese restaurant that he found in a dumpster. Prior to this he was healthy, with no infection of any kind. The attending physician suspects a food intoxication. (4 points)
View a related image A labeled view of this image 2. What organism makes the toxin that could have caused this food intoxication?
Bacillus cereus.
A male patient was admitted to the hospital for intravenous antibiotic treatment of folliculitis. He began a second course of antibiotics, this time ampicillin, a few days ago and has begun suffering from diarrhea, abdominal cramps, and fever. Blood work reveals an increase in his white blood cell count. Stool samples were found to contain patches of colonic epithelium. The infectious agent was confirmed to be a gram-positive, spore-forming bacillus by inoculating onto cycloserine-cefoxitin fructose agar and performing an enzyme immunoassay to confirm the presence of toxins A and B, generated by the microbe, in the stool. (6 points) What is this disease called?
Antibiotic-induced colitis is a good general term. There are many people with antibiotic-associated diarrhea who do not have colitis. Sometimes this is called pseudomembranous colitis (since pseudomembranes may be seen on the colonic surface).
- What is the significance of the patches of epithelium?
o Pseudomembranes which are sloughed off during the infection. What treatment would you prescribe? Oral rehydration therapy, metronidazole if therapy is necessary, oral vancomycin in refractory cases
Case
A young woman, who has just returned from a vacation in South America, is admitted to the emergency room with vomiting and severe diarrhea, which has been going on for about 3 hours and is accompanied by muscle cramps and a severe thirst. On examination, the patient is found to have a lowered blood pressure and rapid heart rate
her eyes appear somewhat sunken. She is producing copious amounts of “rice water stools” (odorless and flecked with mucus) which contain gram-negative, curved, motile bacteria with a brisk, darting motility. (6 points) What led you to this diagnosis? (2 points)
Cholera
A college student presents to the outpatient medical clinic for evaluation of diarrhea and abdominal discomfort. His symptoms began 1 week ago, and he has subsequently had up to three loose bowel movements a day, plus crampy abdominal pain. The patient states that he has “not been able to hold anything down” during this time except some fluids. The last meal he ate, prior to infection, was at a fraternity cookout where he had chicken. Culture of the stools on a variety of media including Hektoen agar, Yersinia agar, and MacConkey sorbitol agar were all normal, but Campylobacter agar revealed a slightly-curved gram-negative rod. No occult blood was seen in the stools. This organism is found in normal fecal contamination from chickens and reflects unsanitary and unhygienic handling of food products. (4 points) What organism is likely to be causing the patient’s symptoms?
Campylobacter jejuni