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Year : 2014  |  Volume : 62  |  Issue : 3  |  Page : 341--342

'Hot-cross bun' and 'inverse trident sign' in progressive multifocal leukoencephalopathy with HIV seropositivity

Rajendra S Jain, Kadam Nagpal, Shankar Tejwani 
 Department of Neurology, Sawai Man Singh Medical College, Jaipur, Rajasthan, India

Correspondence Address:
Rajendra S Jain
126, Janakpuri II, Imli Ka Phatak, Jaipur - 302 005, Rajasthan

How to cite this article:
Jain RS, Nagpal K, Tejwani S. 'Hot-cross bun' and 'inverse trident sign' in progressive multifocal leukoencephalopathy with HIV seropositivity.Neurol India 2014;62:341-342

How to cite this URL:
Jain RS, Nagpal K, Tejwani S. 'Hot-cross bun' and 'inverse trident sign' in progressive multifocal leukoencephalopathy with HIV seropositivity. Neurol India [serial online] 2014 [cited 2021 Mar 9 ];62:341-342
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A 42-year-old male human immunodeficiency virus (HIV) positive, presented with 2-month history of subacute onset, progressive ataxia of gait and limbs, dysarthria and dysphagia for both solids and liquids with nasal regurgitation. Otherwise history was negative. There was history of multiple sexual contacts in the past. On examination, patient was hemodynamically stable, conscious and well oriented. Neurological examination revealed mini-mental state examination score of 24/30, bilateral gaze evoked nystagmus, diminished palatal movements with absent gag reflex on right side, normal tone and motor power, brisk deep tendon reflexes, and bilateral cerebellar signs (gait and limb ataxia). CD-4 cell count was 160 cells/μl. Cerebrospinal fluid examination revealed normal cell count, elevated protein (100 mg/dl) and positive cerebrospinal fluid-polymerase chain reaction (CSF- PCR) for JC virus. Tests for other opportunistic infections were negative. Magnetic resonance imaging (MRI) brain showed an 'inverse trident sign' in upper pons and a 'hot-cross bun' sign in middle and lower pons [Figure 1]. In addition, there were associated asymmetric T2-weighted hyperintensities in middle and inferior cerebellar peduncles and bilateral parieto-occipital regions without any contrast enhancement [Figure 2]. MR spectroscopy showed a reduced N-acetyl aspartate (NAA) and slightly elevated choline/creatine ratio [Figure 3].{Figure 1}{Figure 2}{Figure 3}

Hot-cross bun sign is frequently seen in cerebellar type of multiple system atrophy (MSA) and spinocerebellar ataxia (SCA), due to selective loss of myelinated transverse pontocerebellar fibers and neurons in pontine raphe with preservation of pontine tegmentum and corticospinal tracts. Other clinical conditions where hot-cross bun sign is rarely reported include progressive multifocal leukoencephalopathy (PML) in HIV seropositive, variant-Creutzfeld-Jakob disease (CJD), secondary Parkinsonism and cerebrotendinous xanthomatosis. [1] Trident sign has been reported in Wilson's disease and central pontine myelinolysis (CPM), but never in PML to the best of our knowledge. The plausible mechanism for a 'trident sign' has been preferential involvement of transverse pontine fibers. [2] We postulate similar mechanism for an 'inverse trident sign' as involvement of transverse pontine fibers is clearly evident. Moreover, our patient had predominant involvement of posterior fossa structures similar to the findings reported by others. [3],[4] No specific treatment is available for PML in HIV patients currently; however, early administration of highly active anti-retroviral therapy (HAART) is recommended to prevent this dreaded complication.


1Jain RS, Sannegowda RB, Agrawal A, Hemrajani D, Jain R, Mathur T. ′Hot cross bun′ sign in a case of cerebrotendinous xanthomatosis: A rare neuroimaging observation. BMJ Case Rep 2013;2013.
2Biotti D, Durupt S. A trident in the brain, central pontine myelinolysis. Pract Neurol 2009;9:231-2.
3Yadav R, Ramdas M, Karthik N, Kulkarni GB, Dawn R, Kumar MV, et al. "Hot cross bun" sign in HIV-related progressive multifocal leukoencephalopathy. Neurol India 2011;59:293-4.
4Padmanabhan S, Cherian A, Iype T, Mathew M, Smitha S. Hot cross bun sign in HIV-related progressive multifocal leukoencephalopathy. Ann Indian Acad Neurol 2013;16:672-3.