Mesenteric lymphadenitis as a presenting feature of Whipple's disease: Value of PCR analysis

Contribution of PCR to Differential Diagnosis between Patients with Whipple Disease and Tropheryma whipplei Carriers

Differentiation between Whipple disease (WD) patients and patients carrying Tropheryma whipplei but suffering from disease other than WD ("carriers") remains complex. We aimed to evaluate T. whipplei PCR among patients with WD and carriers in a large cohort at our referral clinical microbiology laboratory. This is an observational retrospective cohort study, including all patients between 2008 and 2020 with at least one positive result for T. whipplei using the real-time PCR RealCycler TRWH-UX kit. A total of 233 patients were included: 197 were considered carriers, and 36 had WD. Among the WD patients, 32 underwent biopsies, of which 18 (56%) had a positive periodic acid-Schiff (PAS) staining. Among the 27 duodenal biopsy specimens, 13 (48%) were PAS positive. PCR results before antibiotic treatment were positive in both feces and saliva in 16/21 WD (76%) patients and 68/197 (35%) carriers (P < 0.001). Duodenal biopsy specimens yielded positive PCR in 20/22 (91%) WD patients and 27/72 (38%) carriers (P < 0.001). The cycle threshold (C_T) value detected in duodenal biopsy specimens from WD patients was significantly lower than that of carriers (P < 0.001), regardless of the PAS staining results. For a diagnosis of WD, duodenal PCR sensitivity and specificity at a C_T value below 30 were 52.4% and >99.9%, respectively. The high specificity of duodenal PCR with low C_T values may help confirming the diagnosis of WD, especially in patients with negative PAS results in digestive biopsy specimens, who represent half of all patients. A low PCR C_T value from a duodenal biopsy specimen provides valuable guidance, especially in patients with PAS-negative results.

An unusual presentation of Whipple’s disease: adenopathies, polyarthralgia and dermatomyositis-like symptoms

Whipple’s disease (WD) is a rare systemic disease caused by gram-positive bacillus bacteria that invades multiple organs mainly the intestinal epithelium. Its manifestation is not only limited to the gastrointestinal tract but it also affects the joints, muscle and skin. This is a case of a 54-year-old male patient with a medical history of chronic arthritis presenting with bilateral progressive calves pain, anterior tibial hyperpigmentation, joints pain, anemia and weight loss. He was misdiagnosed as rheumatoid arthritis, for which he was treated by immunosuppressors for several years with no amelioration. After advanced investigations, he was found to have multiple retroperitoneal and mesenteric adenopathies, with an incidental finding of a mesojejunal mass during laparoscopy, from which the biopsies revealed the presence of histiocytosis and numerous intra-cytoplasmic particles with positive periodic acid–Schiff (PAS) suggesting the diagnosis of WD. Endoscopy was done and intestinal histology with polymerase chain reaction (PCR) test confirmed the diagnosis of WD. The patient was then treated with antibiotics (ceftriaxone and trimethoprim-sulfamethoxazole) with a remarkable clinical amelioration. To be aware of WD as a potential etiology behind malabsorption, musculoskeletal and skin abnormalities, is the first step in order to establish the diagnosis and provide adequate treatment, thus, improving the patient’s quality of life. WD is a rare, without antibiotic treatment deadly systemic infectious disease caused by the ubiquitary Gram-positive bacterium Tropheryma whipplei. This article aims to report a case marked with dermatomyositis like presentation that had a missed and delayed diagnosis.

Whipple's Disease Affecting Ileal Peyer's Patches: The First Case Report

Whipple's disease is a rare chronic systemic bacterial infectious disease which can affect multiple organs, with a wide clinical spectrum encompassing many symptoms presenting in various forms and combinations. In the cases where the gastrointestinal tract is implicated, the more frequent localizations involve the small bowel, especially the duodenum. A case of a 67-year-old man who underwent clinical investigation after presenting with a progressive weight loss and showing a hypercapting right paracoeliac adenopathy at PET-CT scan is reported herein. A gastroscopy and a colonoscopy were done. The biopsies of the endoscopically normal ileal mucosa encompassed some submucosal Peyer's patches. Histological examination of this lymphoid tissue revealed several foamy macrophages which turned out positive on periodic acid-Schiff special staining. Polymerase chain reaction of the microdissected lymph follicles allowed for confirming Whipple's disease diagnosis. A targeted antibiotic treatment administrated to the patient led to a rapid clinical improvement. This finding of a previously unreported localization of infected macrophages in Whipple's disease suggests that sampling the organized mucosal-submucosal lymphoid tissue may increase the diagnostic yield in endoscopic biopsies.