Figure 4.

Fatal co-infections

(A–C) 5-year-old girl (case 8) presented with fever, headache, and seizures. Initial MRI showed an acute small left frontal infarct on axial FLAIR imaging (A; arrow). 5 days later she had extensive leptomeningeal enhancement in the basilar cisterns and perisylvian regions on postcontrast T1-weighted imaging (B; arrows). Findings progressed and, 3 weeks after presentation, markedly reduced diffusion on diffusion trace imaging (C; arrows) and oedema of the brain parenchyma were observed. The patient's brain biopsy was positive for SARS-CoV-2 viral inclusions on electron microscopy and positive for tuberculosis granulomata despite no tuberculosis contact. (D–F) A 5-year-old girl (case 9) presented with encephalopathy and acute respiratory distress and became septic with meticillin-resistant Staphylococcus aureus and varicella zoster virus infections, both of which were culture positive in the blood and CSF. She had multiple small foci of reduced diffusion on axial diffusion trace imaging, in keeping with microinfarcts (D, E; arrows), some of which had associated microhaemorrhage (F; arrow). This patient died 15 days after symptom onset. (G–J) A 6-year-old boy (case 10) with no previous comorbidities presented with scattered T2 hyperintensities in the supratentorial white matter. He also had marked choroid plexitis (G; arrowheads) and foci of ring enhancement on T1 postcontrast imaging, in keeping with small abscesses (H; circles). There was minimal ependymal enhancement (H; arrowhead). Reduced diffusion was noted in the affected choroid and abscesses (not shown). 2 weeks later, axial T2-weighted imaging showed extensive and rapid progression involving multiple supratentorial and infratentorial compartments with ependymal invasion around the fourth ventricle (I; arrowhead), the basal ganglia, and the lateral ventricles (J; arrowhead). These areas also showed enhancement and reduced diffusion (not shown). Mycobacterium tuberculosis infection was confirmed at open biopsy. (K–O) A 16-year-old boy (case 11) presented with encephalopathy, fever, sinusitis, and meningismus, and Fusobacterium necrophorum and Streptococcus constellatus co-infections in the blood and CSF. At presentation he had multivessel stenoses on his magnetic resonance angiogram, most markedly involving the anterior and middle cerebral arteries (K; arrows), and there was associated vessel wall enhancement on postcontrast arterial wall imaging (L; arrow) and multiple vascular territory infarcts on the apparent diffusion coefficient map and diffusion-weighted trace image (M, N; arrows), features all in keeping with multivessel vasculitis. This condition progressed to multiple regional infarctions as shown on CT at day 5 (O; arrows). FLAIR=fluid-attenuated inversion recovery.