Susceptibility to mycobacterial infection in VEXAS syndrome

OBJECTIVES

VEXAS is a recently described acquired auto-inflammatory and hematologic syndrome caused by somatic mutations in UBA1. To date, VEXAS is not a recognized cause of acquired immunodeficiency.

PATIENTS AND METHODS

Two of our 10 VEXAS patients developed a disseminated Mycobacterium avium infection. To shed light on this observation, we retrospectively studied all patients with disseminated non-tuberculous mycobacterial infections (NTMi) seen at our institution over 13 years. Inclusion criteria were a positive blood/bone marrow culture, or 2 positive cultures from distinct sites, or one positive culture with 2 involved sites.

RESULTS

patient 1 presented with fever, rash, orbital cellulitis and lung infiltrates. Patient 2 presented with fever and purpura. In both cases, Mycobacterium avium was identified on bone marrow culture. Twenty cases of disseminated NTMi were reviewed. Among 11 HIV-negative patients, three had chronic immune-mediated disease; three had untreated myeloid neoplasm; two had VEXAS; one had undergone kidney transplantation; one had GATA-2 deficiency; and one had no identified aetiology. None had lymphoid neoplasia or had undergone bone marrow transplantation. HIV-negative cases had higher CD4 counts than HIV-positive patients (median CD4: 515/mm3  vs 38/mm3, p< 0.001). Monocytopenia was present in seven cases. At 2 years, six patients had died, including both VEXAS patients.

DISCUSSION

VEXAS patients have an intrinsic susceptibility to disseminated NTMi, which may result from monocytic dysfunction. NTMi can mimic VEXAS flare. Clinicians should maintain a high suspicion for opportunistic infections before escalating immunosuppressive therapy. Further studies are needed to confirm and better decipher the herein reported observations.

A case report of unilateral cerebral vasculitis in adults: keep in mind Lyme neuroborreliosis

BACKGROUND

Lyme neuroborreliosis (LNB), due to infection of the nervous system by the spirochete Borrelia burgdorferi, occurs in 15% of Lyme disease cases. However, neurovascular involvement is uncommon, especially recurrent stroke related to cerebral vasculitis in the absence of CSF pleocytosis.

CASE PRESENTATION

We report the case of a 58-year-old man without any medical history who exhibited recurrent strokes in the same vascular territory (left internal carotid). Multiple biological screening, neuroimaging methods, and cardiovascular examinations failed to provide a diagnosis and treatment that could have prevented recurrences. Finally, B. burgdorferi sensu lato serology testing in blood and cerebrospinal fluid enabled diagnosis of LNB, in relation to a cerebral vasculitis. The patient experienced no further stroke after four weeks of doxycycline treatment.

CONCLUSION

B. burgdorferi central nervous system infection must be considered in case of unexplained recurrent and/or multiple strokes, especially if cerebral vasculitis is suspected or demonstrated on neuroimaging.