Snapshot A 35-year-old man presents to the dermatology clinic for a rash. He reports that these spots have been on his skin for about 2 months now since he returned from a work-stay program in South America. There he interacted with animals and occasionally tried exotic foods, such as the armadillo. On physical exam, there are multiple well-circumscribed erythematous plaques with raised borders and central hypopigmentation. There is loss of sensation over the plaques. He is started on a long course of antibiotics. Introduction Classification Mycobacterium leprae a non-motile, acid-fast bacillus prefers cool temperatures transmission respiratory via nasal mucosa via armadillo reservoirs Epidemiology incidence more common in Southeast Asia and South America location affects skin and peripheral nerves risk factors travel to endemic countries contact with others with leprosy contact with or consumption of reservoirs such as armadillos Pathogenesis the bacteria grows in cool regions, such as the skin and peripheral nerves infects macrophages, Schwann cells, and keratinocytes lepromatous Hansen disease weak cell-mediated immunity humoral Th2-type immune response high burden of bacteria in lesions tuberculoid Hansen disease strong cell-mediated immunity Th1-type immune response low burden of bacteria in lesions Associated conditions lepromatous Hansen disease tuberculoid Hansen disease erythema nodosum Prognosis slow progression that may develop over months or years may have intermittent acute leprosy reactions lepromatous type is more severe Presentation Symptoms lepromatous Hansen disease diffuse rash tuberculoid Hansen disease multiple discrete lesions Physical exam patients often present with overlapping findings peripheral neuropathy foot drop facial nerve palsy contractures or hand or feet loss of sensation lepromatous Hansen disease leonine facies (lion-like) thickened foreheard, ears, eyebrows, and cheeks diffuse plaques and nodular skin lesions symmetrically distributed may be erythematous or hypopigmented without sharp borders tuberculoid Hansen disease multiple discrete erythematous plaques with central hypopigmentation and raised discrete borders plaques often have loss of sensation hairless dry with some scale Studies Labs tissue polymerase chain reaction (PCR) may test as falsely positive on VDRL testing Biopsy or slit-skin smear acid-fast bacilli granulomas Making the diagnosis based on clinical presentation and tissue diagnosis Differential Morphea distinguishing factor also presents with thickened skin but usually does not involve peripheral nerve damage Vitiligo distinguishing factor also presents with hypopigmentation but without peripheral nerve damage or raised borders Treatment Medical dapsone and rifampin indication tuberculoid and lepromatous types clofazimine indication added therapy for lepromatous types Complicatons Permanent nerve impairment Deformities
QUESTIONS 1 of 4 1 2 3 4 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 Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.MC.75) A 29-year-old man who recently emigrated from South America presents complaining of a patch of numbness on his skin. He reports that the area has appeared paler than the surrounding skin for a long time. He also has had several cuts and burns near the area, but has no recollection of when the injuries took place and did not feel any pain at the time. On physical exam, you palpate an enlarged ulnar nerve at the elbow. Relevant additional findings from your physical exam are shown in Figure A. You order a biopsy from the edge of the lesion (Figure B). Which of the following most likely caused his disease? Review Topic QID: 106735 FIGURES: A B 1 Sarcoidosis 8% (2/24) 2 Mycobacterial infection 58% (14/24) 3 Sporothrix schenckii 21% (5/24) 4 Contact dermatitis 0% (0/24) 5 Poxvirus infection 8% (2/24) M1 Select Answer to see Preferred Response PREFERRED RESPONSE 2 Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK