S3490 The Great Masquerader: Whipple’s Disease Presenting as Sarcoid-Like Granulomas

Abstract

Introduction: Whipple’s disease (WD) can be mistaken for sarcoidosis given its overlapping symptoms and presence of granulomas. We present a patient with history of sarcoidosis with progression despite immunosuppression, later found to have WD. Case Description/Methods: A middle-aged female presented with abdominal pain, vomiting, diarrhea, and weight loss for three years. She had AKI, hypercalcemia, and renal biopsy with non-caseating granulomas leading to sarcoidosis diagnosis. She improved with steroids and methotrexate. Workup for mediastinal lymphadenopathy and pulmonary disease was negative. Months later, GI symptoms recurred. EGD and colonoscopy with biopsies were unremarkable. MRE and gastric emptying study were normal. She received several courses of IV steroids for presumed sarcoidosis flares. On admission, a PET scan had intense FDG avidity in the small and large bowel and no extraintestinal uptake. IV solumedrol was initiated for presumed flare with plans to initiate outpatient TNF inhibitor therapy. However, she was readmitted for failure to thrive. Push enteroscopy revealed friable mucosa in the duodenum with biopsies showing numerous foamy histiocytes, distended villi with lipoid vacuoles, and positive periodic acid Schiff (PAS), consistent with WD. Importantly, no granulomas were identified. She was started on IV ceftriaxone with symptomatic improvement. Discussion: WD is a rare, systemic bacterial infection caused by T. whipplei and presents with symptoms including diarrhea, weight loss, and vomiting. Diagnosis is challenging as it can mimic sarcoidosis with granulomas found in multiple organs and responds to steroids initially. In extraintestinal WD, PAS is often negative due to low density of T. whipplei; thus, it is vital to use PCR or electron microscopy to rule out WD in such cases. While it is possible that the patient had sarcoidosis and later developed WD in the setting of immunosuppression, the lack of typical hilar and mediastinal lymphadenopathy and only brief improvement in symptoms with steroids, argue against sarcoidosis. Antibiotics are the treatment for WD; however, patients on immunosuppressive therapy before antibiotics must be monitored for IRIS. Prompt diagnosis and treatment of WD is necessary to prevent endocarditis, CNS manifestations, and death. WD should be considered in the differential diagnosis of sarcoidosis, particularly in steroid-unresponsive disease.