Invasive fungal rhinosinusitis (FRS) is a rare but intractable infectious disease of the sinonasal region with destructive direct infiltration into surrounding tissues, such as the bone, orbit and brain, and potential dissemination to systemic organs. Symptomatic assessments and imaging are frequently not sufficiently diagnostic, and histopathological examination is essential for definite diagnosis of FRS. We herein report a case of chronic invasive FRS (CIFRS) in a 58-year-old Japanese male with end-stage diabetic nephropathy that required maintenance dialysis after graft rejection of living kidney transplantation. His initial main clinical presentation was sinus gangrene, which gradually progressed from the paranasal sinus to the nasal septum and oral palate, but not towards the intracranial or orbital region, for two months. The patient was first strongly suspected to have extranodal natural killer/T cell lymphoma (ENKTL), nasal type, a subtype of malignant lymphoma, based on the macroscopic appearance of the gangrene, expansion pattern and high serum soluble interleukin-2 level; however, repeated biopsies and eventual resection led to diagnosis of CIFRS due to Aspergillus niger and Mucor . The disease was improved by surgical resection in combination with antifungal pharmacologic treatment with liposomal amphotericin B and voriconazole. CIFRS typically occurs in immunocompetent patients and shows intracranial progression, but this case shows that atypical CIFRS with an uncommon expansion pattern can occur in an immunodeficient patient.

Ruxolitinib is a selective JAK1/2 inhibitor that is widely used for the treatment of myeloproliferative neoplasms (MPNs), including myelofibrosis and polycythemia vera (PV). Despite its clinical efficacy for MPNs, ruxolitinib possesses immunosuppressive properties that potentially increase the risks for opportunistic infection, such as mycobacterium tuberculosis (MTB) infection, and reactivation of occult viral infection. Herein, we report the case of a 76-year-old male with PV who developed tuberculosis peritonitis under ruxolitinib therapy for 28 weeks. While previous studies and case reports have suggested an increased risk of MTB infection of various organs during ruxolitinib treatment of MPNs, this case is apparently the first of tuberculosis peritonitis in a patient with MPN treated with ruxolitinib. A review of previous case reports suggests the need for careful observation for MTB from the relatively early phase of ruxolitinib treatment, given that the median duration from the start of ruxolitinib treatment to the emergence of MTB was 20 weeks (range: 3-88 weeks). Clinicians should consider tuberculosis peritonitis as a differential diagnosis when patients with MPN treated with ruxolitinib develop infectious abdominal symptoms.