Longitudinally Extensive Myelitis Associated With Neurotoxoplasmosis in an Hiv Patient: A Rare Case Report and Diagnostic-Therapeutic Challenge

A 48-year-old man, former cocaine user with a history of ocular toxoplasmosis in 2022, presented with significant weight loss, holocranial headache accompanied by photophobia, phonophobia, nausea, as well as a subacute picture of paresthesia and proximal paraparesis of the lower limbs, constipation, and urinary retention, evolving to hospitalization due to suspected spinal cord compression. During investigation, he had a seizure, and HIV infection was diagnosed, with a viral load of 70,000 copies/mL and CD4 count of 60 cells/mm³, suggesting possible neuroinfection. Cerebrospinal fluid analysis revealed lymphomononuclear pleocytosis, hyperproteinorrhachia, and slightly reduced glucose, with PCR positive for Toxoplasma gondii . Neuroimaging findings demonstrated an expansive left temporo-occipital brain lesion and a longitudinally extensive intramedullary lesion from T6 to T12, both showing post-contrast enhancement and necrotic areas. The patient received initial therapy for neurotoxoplasmosis with sulfamethoxazole-trimethoprim, later switched to clindamycin, pyrimethamine, and folinic acid due to hepatotoxicity. He showed significant clinical and radiological improvement after three weeks, with marked reduction of cerebral and spinal lesions on follow-up MRIs, consolidating the diagnosis based on therapeutic response. Complications included a pulmonary thromboembolism episode, seizure controlled with levetiracetam, hyponatremia suggestive of SIADH, and urinary tract infection with epididymitis. This case highlights the rare association between longitudinally extensive myelitis and neurotoxoplasmosis in an immunosuppressed HIV/AIDS patient, an uncommon cause of myelitis in this context, representing a diagnostic and therapeutic challenge, especially in cases of delayed HIV testing and antiretroviral therapy initiation. The favorable outcome after specific treatment underscores the importance of considering toxoplasmosis as a possible etiology of atypical spinal cord involvement and reinforces the value of a therapeutic test in diagnostic uncertainty, particularly in endemic regions.