CASE 50 (April 2010)
The patient is a 42-year-old, housewife, who lives in a rural area. She has no history of disease. She consults due to abdominal pain, localized in right upper quadrant radiating to back, accompanied by nausea, malaise and headache. Generalized edema. She describes dyspnea. The patient reports dysphagia and catarrhal symptoms until two weeks ago.
On physical examination: regular general condition. Blood pressure: 169/86 mm Hg., heart rate: 56 bpm, respiratory frequency: 16. There is no fever. Bipalpebral edema. There are not lymphadenopathy or organomegaly. Normal cardiopulmonary auscultation. There are not skin lesions. On abdominal palpation there is pain in right upper quadrant. Edema in lower limbs. Presumptive diagnosis on admission: cholelithiasis, cholecystitis, hypertension.
Laboratory tests: complete blood count and coagulation tests: normal. Serum creatinine: 0.9 mg/dL; BUN: 12 mg/dL; creatinine clearance: 75.62 mL/min. Total cholesterol: 204 mg/dL; LDL: 133 mg/dL; triglycerides: 129 mg/dL. Glycemia: 67 mg/dL. Serum albumin: 3.0 g/dL. C3: 36 (90-180), C4: 12.6 (10-40), ANAs and ANCAs: negative; anti-DNA: negative. Viruses B y C: negative. HIV: negative. Urinalysis: Proteins: 500 mg/dL, pH: 6.5; 5-6 leukocytes: 5-6 hpf, erythrocytes: 8-12 hpf, granular casts: 1-2 hpf, nitrites: negative. Proteinuria: 1.98 g/24h, volume: 3,330 mL.
Chest Rx: loss of costophrenic angles. Abdominal ultrasound: without cholecystitis, normal-appearing kidneys. Echocardiography: ejection fraction: normal, signs of hypertensive heart disease, moderate mitral regurgitation, no vegetations.
On diagnostic thoracentesis the pleural fluid is exudate type, with few lymphocytes and ADA negative.
A renal biopsy is undertaken. See the images.
Figure 1. H&E, X100.
Figure 2. H&E, X400.
Figure 3. H&E, X400.
Figure 4. H&E, X400.
Figure 5. Methenamine-silver stain, X400.
Figure 6. Masson's trichrome stain, X400.
Figure 7. PAS, X400.
Figure 8. Direct immunofluorescence using antiserum to IgG, X400.
Figure 9. Direct immunofluorescence using antiserum to C3, X400.
Direct immunofluorescence for IgA, IgM, and C1q: Negative.
What is your diagnosis?