Snapshot A 40-year-old woman presents to the emergency room with a week of fever, cough, and hemoptysis. She has a history of HIV and has been noncompliant with her medications and has a history of tuberculosis that was adequately treated. She reports feeling increasing fatigue. A chest CT shows nodules with a halo sign. A bronchoalveolar lavage with biopsy eventually reveals fungus with septate hyphae branching at acute angles invading into lung tissue. (Invasive aspergillosis) Candida albicans Classification yeast with budding and pseudohyphae germ tube formation at 37°C (diagnostic) can be part of normal flora Risk factors immunocompromised status hospital admission, especially in the ICU Clinical syndrome immunocompetent hosts present with skin and mucous membrane infections oral thrush white plaque on the tongue that can be scraped off candidal intertrigo well-demarcated, erythematous, and itchy plaques in the skin folds vulvovaginitis thick "cottage cheese" white discharge itchiness immunocompromised hosts usually present with systemic disease local infection is due to T-cell deficiency while systemic infection is due to neutropenia esophagitis dysphagia and throat pain endoscopy shows white plaques along the esophagus endocarditis associated with IV drug users fevers and a new murmur disseminated/invasive candidiasis fever and septic shock Studies definitive diagnosis requires blood or other tissue culture wet mount with potassium hydroxide prep of vaginal fluid shows yeast with pseudohyphae germ tube formation at 37°C Treatment nystatin local infections azoles local and systemic infections first-line if the fungus is not resistant echinocandins systemic infections first-line due to increased resistance to azoles amphotericin B systemic infections second-line or for pregnant women Cryptococcus neoformans Classification urease-positive monomorphic encapsulated yeast with 5-10 μm narrow budding transmitted via inhalation and found in soil and pigeon droppings Risk factors immunocompromised status HIV/AIDS patients Clinical syndrome cryptococcosis cryptococcal meningitis cryptococcal encephalitis presents with fevers, headaches, and generalized malaise Studies and imaging head imaging with computed tomography (CT) or magnetic resonance imaging (MRI) soap bubble lesions variable enhancing lesions hydrocephalus detection of capsular antigen in serum or cerebrospinal fluid (CSF) latex agglutination test CSF studies culture on Sabouraud agar India ink stain shows yeast with clear halos mucicarmine shows yeast with red inner capsules Treatment amphotericin B + flucytosine for 10-14 days fluconazole after treatment with amphotericin B and flucytosine maintenance and suppressive therapy Aspergillus spp. Classification most commonly Aspergillus fumigatus monomorphic fungus with septate hyphae branching at acute angles (45 degrees) found in soil and decomposed material transmission via inhalation of spores Risk factors immunocompromised status hematologic malignancy asthma pre-existing lung disease Clinical syndrome invasive aspergillosis invasive infection of the lung causes persistent fever and cough with hemoptysis aspergilloma mycetoma ("fungal ball") in pre-existing cavity (i.e., tuberculosis) causes cough with hemoptysis or asymptomatic allergic bronchopulmonary aspergillosis (ABPA) hypersensitivity reaction in patients with cystic fibrosis or asthma causes bronchiectasis and eosinophilia causes cough with hemoptysis, brownish black mucus plugs in expectorate, and wheezing Studies and imaging invasive aspergillosis nodules with halo sign and cavitary lesions on computed tomography (CT) pathologic examination showing invasive hyphae into tissue positive cultures or serology aspergilloma mobile round or ovoid mass on chest CT positive cultures or serology ABPA bronchiectasis on CT elevated eosinophils or IgE in ABPA Treatment invasive aspergilloma voriconazole + amphotericin B first-line caspofungin second-line aspergilloma surgical resection ABPA steroids first-line Mucormycosis Classification Mucor and Rhizopus spp. fungi with irregular, broad, and nonseptate hyphae branching at wide or right angles found in soil and decomposed material transmission via inhalation of spores or direct inoculation through trauma Risk factors diabetic ketoacidosis immunocompromised status trauma or burns Clinical syndrome mucormycosis (rhinocerebral infection) headache congestion sinus pressure and pain black necrotic eschar on face, particular nares or palate Studies and imaging computed tomography (CT) shows air-fluid levels in the sinuses and bony destruction biopsy of affected tissue shows nonseptate hyphae with wide-angle branching Treatment amphotericin B first-line isavuconazole second-line surgical debridement for patients who need it, in addition to antifungals Pneumocystis jiroveci Classification a yeast-like fungus transmission via airborne Risk factors immunocompromised status HIV smoking Clinical syndrome interstitial pneumonia progressive exertional dyspnea chest pain nonproductive cough fever and chills hemoptysis is rare Imaging chest radiograph will show bilateral infiltrates computed tomography will show patchy ground-glass opacities sand pneumatoceles Studies histology with methenamine silver, Diff-Quik, or Wright stain of lung tissue disc-shaped yeast Treatment trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis (CD4+ count < 200 cells/mm3) and first-line therapy corticosteroids severe cases pentamidine, atovaquone, or dapsone second-line therapy if resistant to TMP-SMX or allergic
QUESTIONS 1 of 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Previous Next Lab Values Blood Hematologic Cerebrospinal Sweat, Urine, and BMI Blood, Plasma, Serum Reference Range ALT 8-20 U/L Amylase, serum 25-125 U/L AST 8-20 U/L Bilirubin, serum (adult) Total // Direct 0.1-1.0 mg/dL // 0.0-0.3 mg/dL Calcium, serum (Ca2+) 8.4-10.2 mg/dL Cholesterol, serum Rec: < 200 mg/dL Cortisol, serum 0800 h: 5-23 μg/dL //1600 h: 3-15 μg/dL 2000 h: ≤ 50% of 0800 h Creatine kinase, serum Male: 25-90 U/LFemale: 10-70 U/L Creatinine, serum 0.6-1.2 mg/dL Electrolytes, serum Sodium (Na+) 136-145 mEq/L Chloride (Cl-) 95-105 mEq/L Potassium (K+) 3.5-5.0 mEq/L Bicarbonate (HCO3-) 22-28 mEq/L Magnesium (Mg2+) 1.5-2.0 mEq/L Estriol, total, serum (in pregnancy) 24-28 wks // 32-36 wks 30-170 ng/mL // 60-280 ng/mL 28-32 wk // 36-40 wks 40-220 ng/mL // 80-350 ng/mL Ferritin, serum Male: 15-200 ng/mLFemale: 12-150 ng/mL Follicle-stimulating hormone, serum/plasma Male: 4-25 mIU/mL Female: premenopause: 4-30 mIU/mL midcycle peak: 10-90 mIU/mL postmenopause: 40-250 pH 7.35-7.45 PCO2 33-45 mmHg PO2 75-105 mmHg Glucose, serum Fasting: 70-110 mg/dL2-h postprandial:<120 mg/dL Growth hormone - arginine stimulation Fasting: <5 ng/mLProvocative stimuli: > 7ng/mL Immunoglobulins, serum IgA 76-390 mg/dL IgE 0-380 IU/mL IgG 650-1500 mg/dL IgM 40-345 mg/dL Iron 50-170 μg/dL Lactate dehydrogenase, serum 45-90 U/L Luteinizing hormone, serum/plasma Male: 6-23 mIU/mL Female: follicular phase: 5-30 mIU/mL midcycle: 75-150 mIU/mL postmenopause 30-200 mIU/mL Osmolality, serum 275-295 mOsmol/kd H2O Parathyroid hormone, serume, N-terminal 230-630 pg/mL Phosphatase (alkaline), serum (p-NPP at 30° C) 20-70 U/L Phosphorus (inorganic), serum 3.0-4.5 mg/dL Prolactin, serum (hPRL) < 20 ng/mL Proteins, serum Total (recumbent) 6.0-7.8 g/dL Albumin 3.5-5.5 g/dL Globulin 2.3-3.5 g/dL Thyroid-stimulating hormone, serum or plasma .5-5.0 μU/mL Thyroidal iodine (123I) uptake 8%-30% of administered dose/24h Thyroxine (T4), serum 5-12 μg/dL Triglycerides, serum 35-160 mg/dL Triiodothyronine (T3), serum (RIA) 115-190 ng/dL Triiodothyronine (T3) resin uptake 25%-35% Urea nitrogen, serum 7-18 mg/dL Uric acid, serum 3.0-8.2 mg/dL Hematologic Reference Range Bleeding time 2-7 minutes Erythrocyte count Male: 4.3-5.9 million/mm3Female: 3.5-5.5 million mm3 Erythrocyte sedimentation rate (Westergren) Male: 0-15 mm/hFemale: 0-20 mm/h Hematocrit Male: 41%-53%Female: 36%-46% Hemoglobin A1c ≤ 6 % Hemoglobin, blood Male: 13.5-17.5 g/dLFemale: 12.0-16.0 g/dL Hemoglobin, plasma 1-4 mg/dL Leukocyte count and differential Leukocyte count 4,500-11,000/mm3 Segmented neutrophils 54%-62% Bands 3%-5% Eosinophils 1%-3% Basophils 0%-0.75% Lymphocytes 25%-33% Monocytes 3%-7% Mean corpuscular hemoglobin 25.4-34.6 pg/cell Mean corpuscular hemoglobin concentration 31%-36% Hb/cell Mean corpuscular volume 80-100 μm3 Partial thromboplastin time (activated) 25-40 seconds Platelet count 150,000-400,000/mm3 Prothrombin time 11-15 seconds Reticulocyte count 0.5%-1.5% of red cells Thrombin time < 2 seconds deviation from control Volume Plasma Male: 25-43 mL/kgFemale: 28-45 mL/kg Red cell Male: 20-36 mL/kgFemale: 19-31 mL/kg Cerebrospinal Fluid Reference Range Cell count 0-5/mm3 Chloride 118-132 mEq/L Gamma globulin 3%-12% total proteins Glucose 40-70 mg/dL Pressure 70-180 mm H2O Proteins, total < 40 mg/dL Sweat Reference Range Chloride 0-35 mmol/L Urine Calcium 100-300 mg/24 h Chloride Varies with intake Creatinine clearance Male: 97-137 mL/minFemale: 88-128 mL/min Estriol, total (in pregnancy) 30 wks 6-18 mg/24 h 35 wks 9-28 mg/24 h 40 wks 13-42 mg/24 h 17-Hydroxycorticosteroids Male: 3.0-10.0 mg/24 hFemale: 2.0-8.0 mg/24 h 17-Ketosteroids, total Male: 8-20 mg/24 hFemale: 6-15 mg/24 h Osmolality 50-1400 mOsmol/kg H2O Oxalate 8-40 μg/mL Potassium Varies with diet Proteins, total < 150 mg/24 h Sodium Varies with diet Uric acid Varies with diet Body Mass Index (BMI) Adult: 19-25 kg/m2 Calculator ( ) xy AC 7 8 9 ÷ 4 5 6 × 1 2 3 - 0 . = + Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.MC.9) A 47-year-old male with HIV presents to the emergency department with a 2-week history of dyspnea on exertion. He states that over the past week his symptoms seemed to have worsened and he now is experiencing a non-productive cough and low grade fever as well. He also admits that he recently stopped taking an antibiotic that was prescribed by his infectious disease physician because he could not tolerate the side effects. A chest radiograph is obtained which is demonstrated in Figure F and an arterial blood gas demonstrates a PO2 of 70%. Further labs are obtained and are notable for a CD4+ count of 184 and an LDH of 340. Which of the following figures (A-E) correctly demonstrates the causative organism of this patient's infection? Review Topic QID: 103607 FIGURES: A B C D E F 1 Figure A 51% (94/186) 2 Figure B 10% (19/186) 3 Figure C 16% (30/186) 4 Figure D 11% (20/186) 5 Figure E 11% (20/186) M1 Select Answer to see Preferred Response PREFERRED RESPONSE 1 Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.MC.74) A 55-year-old man, who underwent a kidney transplant 2 years ago, presents in septic shock. He is compliant with his immunosuppressive therapy. He does not use any drugs and is sexually active with one male partner. His complete blood count returns as follows: Hemoglobin: 13.7 g/dL, white blood cell count: 4000 cells/microliter, platelets 250,000 cells/microliter. Of note, from his differential: neutrophils: 10%, lymphocytes: 45%, and monocytes: 7%. His basic metabolic profile is notable for a creatinine remaining at his baseline of 0.9 mg/dL. The patient is started on broad spectrum antibiotics, but his condition does not improve. Fungal blood cultures are obtained and grow Candida species. Which of the following was the most-likely predisposing factor? Review Topic QID: 106651 1 Defective IL-2 receptor 0% (0/6) 2 Decreased phagocytic cell count 67% (4/6) 3 HIV infection 33% (2/6) 4 Failure to take suppressive trimethoprim/sulfamethoxazole therapy 0% (0/6) 5 Renal failure 0% (0/6) M1 Select Answer to see Preferred Response PREFERRED RESPONSE 2 Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.MC.34) A 43-year-old HIV positive male presents with signs and symptoms concerning for a fungal infection. He is currently not on antiretrovirals and his CD4 count is 98. Which of the following candidal infections could be seen in this patient but would be very rare in an immunocompetent host? Review Topic QID: 101493 1 Oral thrush 24% (4/17) 2 Vaginitis 0% (0/17) 3 Intertrigo 12% (2/17) 4 Esophagitis 41% (7/17) 5 Endocarditis 12% (2/17) M1 Select Answer to see Preferred Response PREFERRED RESPONSE 4 (M1.MC.14) A 31-year-old female undergoing treatment for leukemia is found to have a frontal lobe abscess accompanied by paranasal swelling. She additionally complains of headache, facial pain, and nasal discharge. Biopsy of the infected tissue would most likely reveal which of the following? Review Topic QID: 101473 1 Yeast with pseudohyphae 12% (28/243) 2 Budding yeast with a narrow base 12% (30/243) 3 Septate hyphae 16% (39/243) 4 Irregular non-septate hyphae 48% (117/243) 5 Spherules containing endospores 9% (23/243) M1 Select Answer to see Preferred Response PREFERRED RESPONSE 4 Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.MC.188) A 50-year-old HIV-positive male presents to the ER with a two-day history of fever and hemoptysis. Chest radiograph shows a fibrocavitary lesion in the right middle lobe. Biopsy of the afflicted area demonstrates septate hyphae that branch at acute angles. Which of the following is the most likely causal organism? Review Topic QID: 101647 1 Mycobacterium tuberculosis 6% (1/18) 2 Candida albicans 6% (1/18) 3 Pneumocystis jeroveci 6% (1/18) 4 Aspergillus fumigatus 83% (15/18) 5 Naegleria fowleri 0% (0/18) M1 Select Answer to see Preferred Response PREFERRED RESPONSE 4