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Renal disease masquerading as pyrexia of unknown origin
1Department of Nephrology, Bombay Hospital, New Marine Lines, Mumbai, Maharashtra, India.
Indian Journal of Nephrology
|August 21, 2013
Summary
This case study highlights Immunoglobulin G4-related kidney disease (IgG4-RD) as a cause of prolonged fever. Prompt diagnosis via kidney biopsy and targeted immunosuppression led to patient recovery.
Area of Science:
- Nephrology
- Immunology
- Pathology
Background:
- Prolonged fever of unknown origin presents diagnostic challenges.
- Common causes include infections, malignancies, and connective tissue diseases.
- Immunoglobulin G4-related disease (IgG4-RD) is an emerging differential diagnosis.
Observation:
- A 57-year-old diabetic male presented with several months of unexplained fever.
- Initial investigations were inconclusive, necessitating a kidney biopsy.
- Renal biopsy revealed characteristic histopathological findings.
Findings:
- Light microscopy showed expansile storiform fibrosis and dense inflammatory infiltrate.
- Immunohistochemical staining confirmed IgG4-related kidney disease (IgG4-RD).
- Elevated serum IgG4 concentrations supported the diagnosis.
Implications:
- Kidney biopsy is crucial for diagnosing IgG4-RD presenting as fever of unknown origin.
- Treatment with corticosteroids and mycophenolate mofetil achieved clinical remission.
- This case underscores the importance of considering IgG4-RD in complex febrile illnesses.
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