The second patient was a 55-year-old Caucasian male, with a history of symmetric polyarthritis and systemic inflammation (CRP 130 mg/l) without fever, previously diagnosed as seronegative rheumatoid arthritis in 2012. No history of travel or surgery was recorded. Over the years, he was treated with cDMARDs (methotrexate) and bDMARDs (certolizumab, ETN, TCZ, abatacept, and adalimumab).
The disease relapsed with arthritis (synovitis demonstrated by US), fever (39 C), and thoracic discomfort, suspicious for pleurisy in September 2017. Previous treatments provided only a partial clinical benefit; however, the systemic inflammation with CRP ranging from 20 to 40 mg/l persisted. There was not any improvement with the introduction of colchicine. After switching to anakinra, we even registered a clinical worsening with fever, arthritis, laterocervical lymphadenopathy, and thoracic rash along with a higher systemic inflammation (CRP 213 mg/l).
Many infections were excluded (i.e., CMV, EBV, chlamydia, mycoplasma, TB, Salmonella, Shigella, and Borrelia burgdorferi) as well as autoinflammatory diseases (negative genetic tests for Mediterranean fever and no improvement with colchicine and anakinra treatment, as reported) and, initially, WD by negative duodenum histopathology (no signs of PAS-positive granules in the duodenum samples).
In the absence of other diagnosis, the adult onset Still's disease appeared the most probable one. The patient was then treated with steroid 0.5 mg/kg/day, with clinical improvement. Infliximab was started and steroid progressively tapered, but with recurrence of fever and systemic inflammation (CRP 68 mg/l).
Despite the PAS negativity in the duodenal biopsy, the patient was then treated with ceftriaxone, showing a dramatic and rapid clinical and laboratory improvement (Figure 4).
Thus, the duodenal samples, as well as other samples from stool and saliva, collected before the introduction of the antibiotic therapy, were analyzed for T. whipplei by PCR in the Reference Center of Marseille, resulting all positive (Figures 5 and 6). Finally, the patient was treated with doxycycline 100 mg twice daily and hydroxychloroquine 6 mg/kg/day, with no relapse after 6 months.