Image of the month: Measles inclusion body encephalitis

Abstract

We present the postmortem neuropathological findings of a 37-year-old HIV-infected man presenting with stupor and super-refractory status epilepticus. HIV infection had been diagnosed 3 years before in the context of unexplained weight loss and prolonged fever. Viral load was 555,000 copies/mL, and his CD4 count was 9 cells/mm3. He immediately started antiretroviral treatment with good virological but poor immunological response. Three months later, he developed malaise, low-grade fever, and diarrhea. Mycobacterium avium intracellulare (MAI) was isolated in feces and sputum. Despite viro-logic control of HIV infection, CD4 count remained below 100 cells/mm3, and 22 months after MAI treatment he was admitted to the hospital with increased bowel movements, severe hypocalcemia, hypomagnesemia, and hypokalemia. He had also a severe corticosteroid-induced osteoporosis and mild hypothyroidism. After appropriate treatment, he improved progressively. However, 6 months after discharge he consulted the HIV outpatient clinic for ~ 5 days of general malaise, restlessness, tremor, and insomnia. Physical examination revealed distal tremor and akathisia, which was initially attributed to a recent increase of levothyroxine. His state worsened during the following days, and he developed mental cloudiness, dysarthria and dysphagia, bilateral reactive mydriasis, and 38 °C fever. He had tachycardia and tachypnea, left pulmonary hypophonesis, and dry crackles. He rapidly developed acute respiratory failure due to aspiration that required in-tubation and mechanical ventilation. At that moment, the patient presented facial myoclonus and right hemiparesis with pyramidal signs. A brain CT was normal, and lumbar puncture showed an acellular cerebrospinal fluid (CSF). Initial brain MRI revealed T2 signal and FLAIR hyperintensities predominantly in the midbrain tegmentum without gadolinium enhancement, suggestive of Wernicke encephalopathy. High-dose parenteral thiamine was administered without improvement, and the patient became stuporous with persistent facial myoclonus. He developed a super-refractory status epilepticus for 4 weeks with EEG showing diffuse delta-theta slowing with continuous and recurrent bilateral frontotemporal epileptic seizures despite treatment with multiple anti-epileptic drugs, and thiopental- and ketamine-induced coma. All microbiological tests from CSF were negative, including Cryptococcus neoformans, HSV1 and 2, EBV, CMV, HHV6, enterovirus, JC virus, Toxoplasma gondii, and Tropheryma whipplei. Mycobacterium PCR and 16S rRNA gene by PCR were also negative. A bronchoalveolar lavage did not result in any positive microbiological test, including Pneumocystis jirovecii, respiratory virus, S. pneumoniae, L. pneumophila, atypical bacteria, and fungi. Blood cultures were also negative.