Rapid clearance of HCV-related splenic marginal zone lymphoma under an interferon-free, NS3/NS4A inhibitor-based treatment. A case report.

Chronic infection with hepatitis C virus (HCV) may lead to B cell activation and transformation into non-Hodgkin lymphoma (NHL). Molecular mechanisms of B cell transformation by HCV are poorly understood. One of the most common lymphoproliferative disorders in HCV-infected patients is splenic marginal zone lymphoma (SMZL). A case of a 42-years old man, affected by HCV-related SMZL, effectively treated with an IFN-free, NS3-NS4A inhibitor-based regimen, is hereby described. The patient was treated for 16 weeks with faldaprevir, deleobuvir, and ribavirin, achieving a very rapid viral eradication without relevant toxicities. A rapid haematologic response was noted as well, with a statistically significant correlation between viral decay and lymphocyte improvement (coefficient r = 0.55, p = 0.042). The viral clearance led to SMZL cure, even without the use of IFN. Thus, the causative role, played by HCV in SMZL development, is once again reinforced, whereby the antiviral, rather than the anti-proliferative activity of IFN is indirectly proven. A regimen including DAAs should be considered when treating a HCV-related extra-hepatic disease.

Cerebral Infectious Opportunistic Lesions in a Patient with Acute Myeloid Leukaemia: The Challenge of Diagnosis and Clinical Management.

Central nervous system (CNS) lesions, especially invasive fungal diseases (IFDs), in immunocompromised patients pose a great challenge in diagnosis and treatment. We report the case of a 48-year-old man with acute myeloid leukaemia and probable pulmonary aspergillosis, who developed hyposthenia of the left upper limb, after achieving leukaemia remission and while on voriconazole. Magnetic resonance imaging (MRI) showed oedematous CNS lesions with a haemorrhagic component in the right hemisphere with lepto-meningitis. After 2 weeks of antibiotics and amphotericin-B, brain biopsy revealed chronic inflammation with abscess and necrosis, while cultures were negative. Clinical recovery was attained, he was discharged on isavuconazole and allogeneic transplant was postponed, introducing azacitidine as a maintenance therapy. After initial improvement, MRI worsened; brain biopsy was repeated, showing similar histology; and 16S metagenomics sequencing analysis was positive (Veilonella, Pseudomonas). Despite 1 month of meropenem, MRI did not improve. The computer tomography and PET scan excluded extra-cranial infectious-inflammatory sites, and auto-immune genesis (sarcoidosis, histiocytosis, CNS vasculitis) was deemed unlikely due to the histological findings and unilateral lesions. We hypothesised possible IFD with peri-lesion inflammation and methyl-prednisolone was successfully introduced. Steroid tapering is ongoing and isavuconazole discontinuation is planned with close follow-up. In conclusion, the management of CNS complications in immunocompromised patients needs an interdisciplinary approach.

Progressive multifocal leukoencephalopathy (PML) development is associated with mutations in JC virus capsid protein VP1 that change its receptor specificity.

Progressive multifocal leukoencephalopathy (PML), a fatal demyelinating disease caused by JC virus (JCV) infection of oligodendrocytes, may develop in patients with immune disorders following reactivation of chronic benign infection. Mutations of JCV capsid viral protein 1 (VP1), the capsid protein involved in binding to sialic acid cell receptors, might favor PML onset. Cerebrospinal fluid sequences from 37/40 PML patients contained one of several JCV VP1 amino acid mutations, which were also present in paired plasma but not urine sequences despite the same viral genetic background. VP1-derived virus-like particles (VLPs) carrying these mutations lost hemagglutination ability, showed different ganglioside specificity, and abolished binding to different peripheral cell types compared with wild-type VLPs. However, mutants still bound brain-derived cells, and binding was not affected by sialic acid removal by neuraminidase. JCV VP1 substitutions are acquired intrapatient and might favor JCV brain invasion through abrogation of sialic acid binding with peripheral cells, while maintaining sialic acid-independent binding with brain cells.