Apoptosis in post-streptococcal glomerulonephritis

Abstract

and platelets of 260 10/L. Clotting was normal, with a PT of 11 seconds and a PTT of 27 seconds. Urinary protein excretion was 1.7 g/24 h with a measured creatinine clearance of 64 mL/min. Laboratory values were as follows: serum sodium, 136 mmol/L; potassium, 4.3 mmol/L; urea, 8.4 mmol/L; and creatinine, 1.1 mg/dL (97 mol/L). Liver function tests were within normal limits: AST, 32 U/L (normal, 5-45); alkaline phosphatase, 230 U/L (normal, 70-330); and ALT, 24 U/L (normal, 5-40). Corrected calcium was normal at 8.5 mg/dL (2.2 mmol/L; normal, 2.2-2.6 mmol/L) as was serum phosphate at 1.2 mmol/L (normal, 0.7-1.4 mmol/L). Immunologic studies revealed an elevated ASO titer of 1200 IU/mL (normal, 0-200); normal immunoglobulin concentrations; depressed C3, 0.26 g/L (normal, 0.83 to 1.46); and borderline low levels of C4 at 0.19 g/L (normal, 0.20 to 0.52); ANCA, anti-GBM, ANA, and rheumatoid factor were negative. An atypical infection screen was reported as follows: herpesvirus CASE PRESENTATION 16 IU; mycoplasma 16 IU; Coxiella, 8 IU; and Legionella An 18-year-old white female student presented to Hope 8 IU. A throat swab sample taken on admission failed to grow Hospital, Salford, England, two years ago with a four-week any organisms. history of general malaise and weight gain. The illness started Ultrasonography demonstrated two kidneys, 11 cm and with a seven-day episode of anorexia, sore throat, cervical 12 cm in length, with normal echotexture. A chest radiograph lymphadenopathy, and pyrexia. The illness progressed over the reported a cardiothoracic ratio of 15/29 with bilateral prominext three weeks with the development of vomiting, diarrhea, nence of the upper lobe vasculature. The lung fields were otherand headache. One week prior to admission, she noticed swelling wise clear. An electrocardiogram revealed sinus rhythm and of her legs and abdomen; the swelling spread to her face, was otherwise unremarkable. particularly the peri-orbital region. A 10 kg weight gain was The patient was treated with bumetanide, which resulted in noted during the week prior to presentation. Her primary care a good diuresis. Her blood pressure declined to 145/88 mm Hg physician noted her blood pressure to be 170/105 mm Hg, and with the onset of the diuresis. Renal biopsy performed on day urinalysis disclosed 3 proteinuria and 2 hematuria. 5 revealed 11 glomeruli, none of which was sclerosed. All None of the symptoms were referable to the urinary tract. showed a global increase in cells, and the inflammatory infilHer medical history was unremarkable apart from a right lower trate included polymorphonuclear leukocytes. There was no lobe pneumonia two years previously. The patient was a nontuft necrosis, and no crescents were seen. The tubules, interstismoker and was taking no regular medications. tium, and blood vessels all appeared normal. ImmunoperoxiOn examination, the patient weighed 69 kg. She had peridase stains revealed heavy basement membrane and mesangial orbital edema and pitting edema of both ankles. Her blood staining for C3 with some of the basement membrane staining pressure was 160/100 mm Hg. Funduscopy was unremarkable. having a “hump”-like appearance. IgG stained only weakly. No murmurs were audible on auscultation of the precordium, IgM, IgA, C1q, and fibrinogen were negative. Electron microsand the chest was free of rales and rhonchi. copy showed the presence of subepithelial humps; some subenThe abdomen and oropharynx were normal. Dipstick urinaldothelial and mesangial deposits were also present. The pattern ysis revealed 3 protein and 2 blood. Microscopy of the was consistent with post-infectious endocapillary proliferative urine confirmed the presence of hematuria with 100 red cells glomerulonephritis. and 60 white cells/mm. Red cell casts were present. HemogloFourteen days after presentation, the patient was seen in bin was 13.2 g/dL, with a white blood cell count of 6.6 10/L the outpatient clinic. Her blood pressure was 130/80 mm Hg and body weight was 55 kg. She had no peripheral edema; diuretic therapy was discontinued. Dipstick urinalysis showed 1 protein and 1 blood. Serum creatinine was 1.22 mg/dL The Nephrology Forum is funded in part by grants from Amgen, Incorporated; Merck & Co., Incorporated; and Dialysis Clinic, Incorporated. (108 mol/L); creatinine clearance was measured at 55 mL/min. Red cells were noted in the urine but no casts were visualized.