RESUMO
Acute renal failure (ARF) following Chlamydia pneumoniae pneumonia is rarely reported in adults. We present an observation in a 10-year-old child, who had C. pneumoniae pneumonia treated with roxithromycin for a period of 10 days, without any other nephrotoxic drug, in particular nonsteroidal anti-inflammatory drugs. At the end of antibiotic treatment, he presented with asthenia, polyuria, polydipsia, increased plasma creatinine, metabolic acidosis, hypokalemia, and markers of tubular damage. The etiological investigations showed positive C. pneumoniae antibodies, increased serum concentrations of C3 and C4 complement, IgA, and IgG. No uveitis was noted. The diagnosis was tubulointerstitial nephropathy after C. pneumoniae pneumonia. C. pneumoniae pneumonia should be considered a differential diagnosis of community-acquired pneumonia, especially in cases of poor response to conventional antibiotic therapy. It may be associated with tubulointerstitial nephropathy and/or rapidly progressive glomerulonephritis whose severity varies in children as in adults. Early and effective treatment of C. pneumoniae infection with macrolide antibiotics usually provides favorable progression of renal function.