Med Bact. Case Study Q's
A 45-year-old female presented to a Houston, Texas area Emergency Department (ED) one July day with a 7-day history of fevers associated with headache, arthralgias, nausea, fatigue, and neck pain. On initial physical examination, she was tachycardic but afebrile. No rash was noted. Laboratory values were within normal limits and a head computed tomography (CT) was unremarkable. Clinical diagnosis of viral illness was made, and she was discharged from the ED. Two days later, she presented to another ED with worsening confusion, combativeness, dyspnea, and ataxia. The patient's spouse mentioned that the patient had sustained multiple recent bug bites from her pet dogs sleeping in her bed. He acknowledged that the dogs were not up to date on their monthly flea and tick medication. The patient had no recent history of travel, hiking, or outdoor exposure. On examination, the patient was tachycardic (heart rate 135 bpm) and hypotensive (blood pressure 84/53 mm Hg). She was toxic in appearance and a maculopapular rash was noted on her abdomen. No bites or ticks were noted on the patient.
Rickettsia rickettsiaàRocky mountain spotted fever
A 19-year-old woman presented because of the recent onset of breakthrough bleeding (vaginal bleeding or spotting that occurs between menstrual periods). She has been taking the same oral contraceptive Pill for two years, she has not forgotten any pills or had diarrhea or vomiting. She has been with her current sexual partner for four months and has recently stopped using condoms as additional protection. She is otherwise well. On examination the vulva and vagina are healthy and there is no inflammation. There is a small cervical ectropion and profuse mucopurulent discharge from the cervix. There is no tenderness on bimanual vaginal examination and no masses palpable.
Chlamydia trachomatosis Confirm diagnosis using nucleic acid amplification/sequencing Azithromycin is the treatment of choice
A blind 65-year-old man, living in rural Iran, was admitted with respiratory infection, fever, dyspnea, loss of appetite, and myalgia. The patient was treated with outpatient antibiotics a week ago. After admission, the patient was again treated for pneumonia, but there was no improvement despite treatment and the patient was suffering from septicemia symptoms. Radiographic images showed wide mediastinum. Cultures from blood and sputum samples showed large, Gram-positive rods and colonies exhibited a "medusa head" morphology. The treatment was changed to ciprofloxacin, clindamycin, and penicillin.
Bacillus anthracis. This is a rare case of inhalation anthrax acquired naturally. On the second day of treatment, the patient was complicated with jaundice, elevation of liver enzymes, and a significant drop in hemoglobin, hematocrit, and platelet despite lack of obvious bleeding and was complicated with respiratory distress and sepsis and died a week after treatment.
A 50-year-old woman from Pulaski, Virginia, presented to a local clinic with headaches, fever, generalized joint pain, excessive thirst and fluid intake, and a progressing rash on her back. On physical examination, she had a large circular red rash on her back with a bull's-eye appearance, 16 × 18 cm in diameter. Upon questioning, the patient could recall a walk through the woods 3 weeks prior but has not seen any ticks or remember having any tick bites.
Borrelia burgdorferiàLymes disease. Rare but serious cardiac complications can occur (Lyme carditis). Antibiotic treatment with doxycycline, amoxicillin, or cefuroxime. Can lead to arthritis and potential neurological issues if not treated.
A 70-year-old Kuwaiti male with a known history of type 2 diabetes mellitus, hypertension, atrial fibrillation, and sick sinus syndrome status post pacemaker placement (placed approximately a year prior to his presentation) presented to our facility with a chief complaint of a mechanical fall, dizziness, urinary incontinence, intermittent subjective fever, and nausea with transient nonbilious, nonbloody emesis (vomit). The patient's travel history is remarkable for recent trip to Kingdom of Saudi Arabia, where patient acknowledged drinking unpasteurized camel milk. On admission, the patient was febrile with a temperature of 38.9°C. Hemodynamic status was acceptable, as was his respiratory status. A visual exam showed a sluggish, ill-looking elderly male who looked older than his stated age. The physical exam was remarkable as it showed a new pan- systolic murmur. No evidence of infective endocarditis stigmata was observed. No appreciable musculoskeletal ailment or joint pain with active and passive motion was noted. Initial lab tests showed no evidence of leukocytosis or leukopenia. White blood cell differential was unremarkable. Chemistry panel showed mild hyponatremia and hypoglycemia. Imaging studies included acute abdominal series and computed tomography of head, both of which were unremarkable. Two sets of blood cultures as well as a urine culture were performed on admission. The hospital course was remarkable with persistent fever spikes for the first week
Brucella melitensis. Blood culture turned out positive for B. melitensis 11 days after initial collection of sample. 2 weeks into his four-drug regimen, the patient developed an oliguric acute kidney injury, which was attributed to aminoglycoside nephrotoxicity. Gentamicin was thus discontinued. Regrettably, in spite of aggressive treatment, the patient's renal failure worsened, and so he required several weeks of hemodialysis. Two months into his hospital course, the kidney function gradually began to improve and hemodialysis was discontinued. Throughout this period, the patient remained on the three-drug regimen, rifampin, doxycycline, and cotrimoxazole. He remained afebrile throughout the remainder of his hospital course. The patient was subsequently discharged after completing a total of 3 months of antibiotic treatment.
A 20-year-old male college student presents with the main complaints of dysuria and urethral discharge. He denies a history of fever, chills, nausea, or abdominal pain. He has never had a urinary tract infection. He had Neisseria gonorrhea treated 6 months ago with an unknown antibiotic. He has no significant past medical history. The only remarkable findings on the physical examination are urethral meatus erythema, a small amount of urethral discharge with milking, but no epididymal tenderness. Urethral swabs are obtained. Grain stain of expressible discharge reveals numerous polymorphonuclear leukocytes but no identifiable organisms. However, a Giemsa stain reveals inclusion bodies within polymorphonuclear leukocytes.
Chlamydia trachomatis. Some biovars cause STD while others cause trachoma. Doxycyline is antibiotic of choice
A 32-year-old female presented to the emergency department with a few hours' history of shortness of breath and weakness associated with chest tightness, congestion, hoarseness of voice, and difficulty swallowing. The patient had presented 24 hours earlier with the complaint of diplopia (double vision) for one day. The patient denied any ingestion of exotic food, shellfish, raw meat, or raw fish. The patient also denied traveling to any exotic place or recent camping trips. The general workup, including biochemical and hematological investigations, came out to be normal except for a mildly decreased serum calcium (7.9 mg/dl). The magnetic resonance imaging (MRI) scan of the brain was also normal. That day, she was discharged with an outpatient consultation with neurology, but she continued to have persistent diplopia. After a few hours of admission, her breathing started to get worse, she was intubated, placed on mechanical ventilation, and was admitted to the intensive care unit (ICU). On examination, she had a symmetrical weakness in all four limbs, with more in the upper limbs compared to the lower limbs. A lumbar puncture was performed, which also came out to be normal. Her weakness progressively increased and while she was being treated, another case arrived at the hospital with a very similar presentation.
Clostridium botulinum. Four days later, the botulinum toxin test came positive and the patient was started on botulinum antitoxin and the rest of symptomatic treatment was continued. The Centre for Disease Control (CDC) tracked the events related to both these patients and found out that they both had eaten nacho cheese from a gas station the day before the appearance of their symptoms. A total of 10 cases were associated with this source within days and one death was reported.
A 64-year-old man who is already in the hospital for cancer therapy develops severe sepsis. He has an extensive recent medical history that includes cancer treatment that began several years ago and a more recent chronic infection by an extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli that required extensive treatment with multiple antibiotics. Blood cultures taken during the fever grew an anaerobic gram-positive bacillus .
Clostridium difficile. Toxin-mediated infection that often follows previous antibiotic therapy. Exhibits high antibiotic resistance, Fecal-microbial transplant is a valid treatment strategy
A 35-year old man took a 30 foot fall while rock climbing 18 miles in the backcountry of central Idaho. He suffered an open fracture of his left arm as well as severe lacerations and crushing injury. It takes several days for him to be transported to the local emergency department for treatment. Upon arrival at the emergency department, the patient complains of a sharp pain that has developed in the last several hours. He he has a fever, elevated pulse, elevated respiration rate, and is exhibiting signs of shock. His injured arm is cool to the touch with large ecchymotic areas and has a serious discharge from the wound. Gram-stain of tissue aspirate shows large gram-positive rods. Crepitus indicative of gas in the wound can be felt.
Clostridium perfringens infection or gas gangrene. Requires extensive surgery to remove all dead and infected materials as necessary life saving procedure. Penicillin G is the antibiotic of choice.
A 38-year-old man checked in to the emergency department with a chief complaint of jaw discomfort and inability to open his mouth fully for 3 days. He also said he had struck his right shin with a hammer 10 days earlier while attempting to fix his lawn mower. The hammer had penetrated deeply through the skin, and although the wound hurt and bled, he had not sought medical attention. Seven days after the original insult, he started noticing jaw discomfort and the inability to open his mouth completely. On the 3rd day of this discomfort, his wife urged him to seek medical attention.
Clostridium tetaniàTetanus. Tetanus toxin blocks release of inhibitory neurotransmitter GABA resulting in muscle rigidity. Preventable with vaccination
A 31-year-old Caucasian man presented to a walk-in clinic complaining of progressive, exertional shortness of breath. He had moved to Calgary, Alberta, from Nova Scotia, where he had worked on a dairy farm, two years prior. Due to pre-existing congenital valvular heart disease, he was referred to the Adult Congenital Cardiology Clinic at the University of Calgary (Calgary, Alberta). The patient could barely climb one flight of stairs without significant shortness of breath, and had developed orthopnea and paroxysmal nocturnal dyspnea. He described occasional palpitations, but denied any syncopal episodes, chest discomfort or peripheral edema. There were no symptoms suggestive of systemic infection. Upon inspection, the aortic valve, subaortic area and anterior mitral valve leaflets looked as though they had previously been affected by endocarditis. He underwent aortic valve replacement, replacement of the ascending aorta, suture repair of an anterior mitral valve leaflet perforation, and repair of the perimembranous aneurysm of the intraventricular septum. Follow-up at three months after surgery found the patient feeling well, but examination unexpectedly revealed a grade 3 of 6 diastolic murmur. A transthoracic echocardiogram confirmed a moderate to severe paravalvular leak, which, with persistent lymphocytosis, prompted a repeat infectious disease consultation.
Coxiella burnetti. Q-fever. Serology indicated Coxiella infection that was confirmed at a specialized research facility. The patient had a complicated postoperative course, including a right lateral thoracotomy for empyema. He was discharged from hospital six weeks after his second aortic valve replacement. Follow-up at one, three, six and 12 months found the patient doing well, with no evidence of systemic infection and a normal-appearing and normal- functioning aortic valve prosthesis.
A 60-year-old woman was admitted to our hospital with a week history of sudden onset of cutaneous lesion on the second finger in her right hand, accompanied by fever, chills, headache and axillary lymphadenopathy. Physical examination revealed the presence of a vesiculopustular lesion on periungual region of her second finger, lymphangitis on her inner right arm and tender lymph node in her right axilla. Initial antibiotic therapy with amoxicillin clavulanate was ineffective. The patient history includes recent handling of hares
Francisella tularensis. Surgical drainage and a 14-days course of ciprofloxacin was given. We observed a gradual improvement and a follow up evaluation one month later revealed that the patient had recovered with no complications.
A 39 year old gentleman initially presented to a community health centre in Malawi's Lilongwe district with widespread skin lesions on the face, torso and the triceps aspect of the right arm. He was referred to the neighboring district hospital with 'allergies'. The lesions were long-standing and had evolved relatively slowly. He was otherwise well although concerned about patches of anaesthetic skin on his face and on the soles of his feet. He denied any past medical history although his blood pressure was incidentally raised at 150/93 mmHg. He smoked occasionally and drank moderate amounts of alcohol. On examination the gentleman had widespread skin nodules and scaly plaques with characteristically thick dermis on his cheeks and feet. He had thick facial nodules and there was evidence of eyebrow loss. He also had slight discomfort in his right upper quadrant and mild right testicular tenderness and swelling. Due to limited resources, the only suitable laboratory investigations available were a full blood count and urea and electrolytes. The only abnormality was a mildly raised white cell count (12x109/L).
Mycobacterium leprae. The gentleman was assigned a clinical diagnosis of leprosy. Ideally, leprosy should be confirmed by the presence of acid-fast bacilli in skin biopsies or split skin smear. The patient was referred to Kamuzu Central Hospital for treatment with multidrug chemotherapy (100 mg Dapsone, 50 mg Clofazimine and 600 mg Rifampicin for 12 months).
A 63-year-old male presents to the emergency department with complaints of cough/shortness of breath which he attributes to a "nagging cold." He is a retired geologist who recently moved from India to live with his son in upstate New York. Smoked 1⁄2 ppd × 40 years and drinks 6 to 8 beers per day, recently admits to drinking 1⁄2 pint of vodka "every few days" since the passing of his wife 6 months ago. He states he fears this may be something worse after experiencing hemoptysis (bloody cough) for the past 3 days. He also admits to waking up in the middle of the night "drenched in sweat" for the past few weeks. His chart indicates he was in the emergency department last week with similar symptoms and was diagnosed with community-acquired pneumonia and discharged with azithromycin.
Mycobacterium tuberculosis. Intensive prolonged treatment with numerous antibiotics for >20 weeks. TB skin test to everyone exposed to infected individual and prophylactic antibiotic treatment for those that test positive.
On April 2, 2010, a female, 8 years and 11 months of age, a resident of an urban area called San Rafael de Desamparados, located ∼6 km south of downtown San Jose, arrived at the main children's hospital in San Jose, Costa Rica (Hospital Nacional de Niños- [HNN]). At the time of admission, the patient reported clinical symptoms of 7 days of evolution characterized by frontal headache, fever, abdominal pain, and severe myalgia. In the last 3 days, the patient developed a maculopapular rash that started in both forearms and progressed into a generalized exanthema mainly in palms and soles. The mother of the patient denied any recent visit to non-urban areas, not even to the city borders. No other members of the family or neighbor reported symptoms of the disease. Upon admission into the hospital the patient developed hypotension, oliguria, hepatic dysfunction, and coagulopathy, and was immediately transferred into the intensive care unit where assisted respiration was initiated. By April 6, 4 days after hospital admission, all bacterial cultures returned negative. On the same day, a neurologist declared the patient brain dead.
Rickettsia rickettsiaàRocky mountain spotted fever. Requires rapid antibiotic treatment with Doxycycline. Initially, the clinical history did not reveal enough data to guide the physicians to the proper diagnosis and some details may have been overlooked. After the patient's death, the personnel of the pathology service at the HNN interviewed her mother, who referred that the family had moved a few weeks before to a new home and that the girl complained of an insect bite on the abdominal area, where the eschar was later found. She also mentioned that they had a pet dog, but the dog was not at their home any more.
A 10-year-old boy from a hilly village presented in April 2016 with a 3-day history of sudden appearance of a painful brownish raised lesion over the back of his left leg, associated with surrounding redness which was increasing progressively. The child did not have fever or any other systemic complaints. He gave a history of visit to the nearby forest a few days before the appearance of the lesion. On examination, there was an erythematous annular plaque on the back of the left lower leg approximately 6 × 5 cm in size, with a central brownish fluid filled blister [Figure 1]. Induration and tenderness were present over the lesion, and local popliteal lymphadenopathy was seen. In addition, there was a lymphangitic streak on the inner aspect of the thigh [Figure 2a]. The patient also had petechiae over the scapular regions [Figure 2b] and a few maculopapular lesions over the dorsum of the hands and ankle region. Systemic examination was unremarkable
Serology for Borrelia burgoderferi Ospc (23 KDa) antigen was done with enzyme-immunoassay technique. IgM was raised at 4.4 U/ml (normal <0.90), whereas IgG was found to be normal [0.3 U/ml (normal <0.90)], which was indicative of acute infection. Treatment was initiated immediately with doxycycline continued for a total of 3 weeks resulting in the clinical resolution of the lesion
The patient was a young, active-duty, male soldier who presented to the military outpatient clinic with a dark, flat-to-raised rash on his lower abdomen and arms. He stated that he came to the clinic because of concern about a mysterious 3-day-old rash that was sparsely located on his arms and lower abdomen, which appeared to be getting worse. He denied any sensation from the rash, such as burning or itching. The patient also stated that he had a small, painless sore on the left side of his penis that appeared 2 weeks earlier as a large "pimple," from which he was able to express thick white fluid. It then became an open sore over the next several days. He denied any discharge from his penis. Aside from the rash and penile ulcer, he stated that he felt fine and had no other symptoms at this initial visit, although he noted that he felt feverish with body aches 2 to 3 days earlier. Regarding his sexual history, he indicated that he had had unprotected sex in the past few months.
Treponema pallidumàsyphilis Diagnose with • Non-specific serological tests: Venereal disease reference laboratory test (VDRL) and Rapid plasma reagin (RPR) • Specific serological test: Fluorescent treponemal antibody test (FTA) Treat with penicillin
A 7-year-old, previously healthy girl from rural southwestern Colorado presented in August 2012 with 2 days of fatigue and subjective fevers followed by multiple episodes of emesis. There were no known ill contacts, but during the preceding 3 weeks she had played in a crawl space underneath the family's new house and swept a dusty chicken coop that contained mouse droppings. Four days before onset of symptoms, the patient and her family picnicked at a nearby national forest campground, where she found and attempted to bury a dead squirrel with a stick. On the day of admission she had multiple episodes of emesis followed by a generalized tonic-clonic seizure. Upon arrival to the local emergency room, she was confused, had a core temperature of 107°F, and an elevated white blood cell count. Providers instituted cooling measures then transferred the patient to a tertiary hospital. On admission to the hospital, the patient had intermittent delirium and visual hallucinations. Her exam was notable for clear breath sounds and the absence of nuchal rigidity or other signs of meningismus. She developed worsening tachycardia, tachypnea, and hypotension, consistent with septic shock, and was transferred to the Pediatric Intensive Care Unit. At that time, several insect bites were noted on both flanks. She was also noted to have a large, extremely tender left inguinal lymph node without overlying erythema. Blood cultures collected at both the local hospital and the tertiary facility were positive for a gram-negative, bipolar-staining rod.
Yersinia pestis. Polymerase chain reaction (PCR) testing of the blood specimen from the tertiary facility conducted at the state public health laboratory using Laboratory Response Network real-time assays presumptively identified Y pestis. Subsequently, the organism was isolated from blood culture on agar plates and confirmed as Y pestis by bacteriophage lysis. She completed a 10-day course of gentamicin for treatment of bubonic plague and recovered completely.
