Diagnostic Trap of Clear Dialysate: Nocardia Peritonitis Without Abdominal Signs

Introduction: Peritoneal dialysis (PD)-associated peritonitis typically presents with cloudy effluent and abdominal symptoms guiding early diagnosis. However, atypical presentations can delay recognition, especially in frail patients. We describe a rare case of polymicrobial peritonitis due to Nocardia veterana and Actinomyces in a malnourished PD patient with clear dialysate and minimal abdominal findings. Case Description: An elderly female with end-stage kidney disease (ESKD) secondary to biopsy-proven diffuse global glomerulosclerosis had been on peritoneal dialysis (PD) for seven months. One month prior to admission, she underwent PD catheter revision with omentopexy due to poor flow. She presented with one month of generalized weakness, abdominal discomfort, chills, and unintentional weight loss of 50 pounds over three months. An outside hospital evaluation attributed her symptoms to constipation, managed with laxatives. She denied fever, nausea, vomiting, or breaks in sterile technique and reported clear PD effluent. On admission, she appeared severely malnourished with a clean PD catheter exit site and no abdominal or tunnel tenderness. Due to systemic leukocytosis (WBC 15,000/μL with neutrophil predominance) empirical Cefepime and Vancomycin were initiated. PD fluid analysis showed 4,028 WBCs/μL with 64 % neutrophils and 12% lymphocytes. Subsequent white cell counts declined to 702/mcl and 169/mcl on hospital day 3 and 6, respectively. Gram-positive rods were identified on day 3 later confirmed as Actinomyces spp. and Nocardia veterana. Antibiotics were switched to Bactrim and Azithromycin. Given identification of Nocardia the PD catheter was removed, and the patient was transitioned to hemodialysis via tunneled catheter. CT imaging of the chest revealed bilateral pulmonary nodules with concern for systemic Nocardosis. Due to severe malnutrition, a PEG tube was placed. She was discharged to a rehabilitation facility and continued Bactrim monotherapy with plan for one year of treatment due to systemic disease. Discussion: This case highlights the rarity of Nocardia peritonitis, particularly in polymicrobial infection with Actinomyces, a possible commensal or contaminant. It underscores the importance of routine PD fluid analysis—even in patients with clear effluent and minimal abdominal symptoms—when systemic signs of infection are present.