A Family at War—Against <i>Tropheryma whipplei</i> : A Case Series

A 29-year-old woman (case 1) with a 2-year history of arthralgia, pericarditis, fever, weight loss, and elevated inflammatory parameters was admitted to Södra Älvsborg Hospital in Borås, Sweden, in January 2023. Severe thrombocytopenia and anemia were remarkable findings at admission. Transthoracic echocardiography showed vegetations on the aortic valve indicating endocarditis. Initial blood cultures were negative. Diagnostics were expanded with polymerase chain reaction (PCR) testing in blood for <i>Tropheryma whipplei</i> and other unusual pathogens. The PCR in blood was positive for <i>T. whipplei</i>, warranting further investigation. Both positive periodic acid-Schiff (PAS) staining and positive PCR of duodenal biopsy confirmed a diagnosis of Whipple's disease (WD). In addition to WD-associated endocarditis/pericarditis, the patient was diagnosed with bilateral multifocal chorioretinitis, which is a possible manifestation of the disease. WD became suspected even in close relatives, the patient's father and her homozygotic twin, who both had similar manifestations such as pericarditis, arthritis/arthralgia, and gastrointestinal symptoms. Another relative, a sister to the father, presented with gastrointestinal symptoms and arthralgia. "Definitive" WD was confirmed in case 2 and case 3 and "possible" WD in case 4.