Pôster:

Microscopic polyangiitis (MPA) is a necrotizing vasculitis of small vessels, which can attack capillaries, venules and arterioles and is usually associated with anti-neutrophil antibody (ANCA). Neurological impairment, although rare, is possible, with multiple mononeuritis and sensory-motor peripheral neuropathy being more common.

Case report

32-year-old female patient was admitted for investigation of abdominal pain in left hemiabdome and was treated with clindamycin and ceftriaxone for 7 days while awaiting diagnostic elucidation, with no improvement in pain. She performed imaging examinations of the abdomen and the genital tract, without alterations. In addition, she had severe microcytic anemia and hyponatremia. It also evolved with loss of renal function, with sudden worsening of nitrogenous scores. She also presented flaccid tetraparesis without alterations of sensibility or sphincter disorders, initially of upper limbs, with evolution to tetraplegia with arreflexia in the neurological exam. Then, it evolved with bulbar and respiratory muscle impairment, being admitted to the ICU only for surveillance. The patient was treated with methylprednisolone pulse therapy for 3 days followed by pulse therapy with cyclophosphamide, in the context of a rapidly progressive glomerulonephritis, with clinical improvement of renal and neurological conditions. Subsequently, she underwent renal biopsy, which showed acute tubular necrosis, and electroneuromyography with an axonal involvement pattern with motor involvement in the proximal and distal regions, unlike the vasculitis characteristic presentations, and the three diagnostic hypotheses, Guillain-Barré variant and porphyria intermittently acute, refuted respectively by the innocent cerebrospinal fluid and urinary porphyrinogen negative research, and of AMAN, which was given as a diagnosis of the case. It presented ANCA positive, with perinuclear pattern, being the title 1:80, and then ANTI-MPO strongly positive. The patient was diagnosed with MPA and is in the service of rheumatology for monthly pulse therapy with cyclophosphamide.

Conclusion

we report an atypical presentation of patients with MPA and AMAN, since, in vasculitis, neurological involvement is usually sensory/distal motor or multiple mononeuritis. Therefore, the authors draw attention to this rare clinical association, and further studies in the area should be performed.