Spontaneous Bacterial Peritonitis Due to Bacillus licheniformis in an Autosomal Dominant Polycystic Kidney Disease Patient on Peritoneal Dialysis: A Rare Presentation Linked to Avian Exposure

This case report details a rare instance of <i>Bacillus licheniformis</i>-induced peritonitis in a 43-year-old male diagnosed with autosomal dominant polycystic kidney disease (ADPKD) undergoing peritoneal dialysis (PD). The patient presented with acute onset of severe abdominal pain and fever, prompting a microbiological investigation that revealed Gram-positive bacilli. Initial empirical treatment with ceftazidime and vancomycin was followed by targeted vancomycin therapy upon identification of <i>B. licheniformis</i>. The patient's clinical course showed steady improvement, corroborated by a recent history of avian contact. This case underscores the critical consideration of uncommon pathogens and environmental exposures in managing peritonitis among peritoneal dialysis patients.