Progressive multifocal leukoencephalopathy: a challenging diagnosis established at autopsy

Molecular diagnosis of opportunistic infections in the central nervous system of HIV-infected adults in Manaus, Amazonas

Background

Opportunistic infections in the central nervous system (CNS) of people with HIV/AIDS (PLWHA) remain significant contributors to morbidity and mortality, especially in resource-limited scenarios. Diagnosing these infections can be challenging, as brain imaging is non-specific and expensive. Therefore, molecular analysis of cerebrospinal fluid (CSF) may offer a more accurate and affordable method for diagnosing pathogens.

Methods

We conducted extensive real-time PCR testing (qPCR) on CSF to evaluate etiological agents in PLWHA with neurological manifestations. Primers targeting DNA from specific pathogens, including cytomegalovirus (CMV), herpes simplex virus (HSV), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), John Cunningham virus (JCV), Toxoplasma gondii, and human T-lymphotropic virus types 1 and 2 (HTLV-1 and HTLV-2), were used.

Results

Cerebrospinal fluid samples revealed 90 pathogens (36.7%). Toxoplasma gondii was the most frequently detected pathogen, found in 22 samples (30.5%). Other pathogens included Cryptococcus sp. (7.7%), EBV (5.3%), CMV, VZV, and JCV (4.0% each).

Conclusion

Despite antiretroviral therapy and medical follow-up, opportunistic central nervous system infections remain frequent in PLWHA. Herpesviruses are commonly detected, but T. gondii is the most prevalent opportunistic pathogen in our study population. Therefore, molecular diagnosis is a crucial tool for identifying opportunistic infections, even in patients undergoing treatment.

Progressive Multifocal Leukoencephalopathy Misdiagnosed as Neuropsychiatric Systemic Lupus Erythematosus With a Catastrophic Outcome

INTRODUCTION

Progressive multifocal leukoencephalopathy (PML) is a rare infection of the central nervous system due to the reactivation of the John Cunningham polyomavirus. It is commonly a progressive fatal disease with worldwide distribution.

CASE REPORT

We describe a rare case of PML, which was misdiagnosed as neuropsychiatric systemic lupus erythematosus (SLE) with a catastrophic outcome due to delay in diagnosis with superadded cyclophosphamide therapy.

CONCLUSION

There are several lessons taught from our case. Firstly, in patients with autoimmune disorders who are strongly immunosuppressed, the new onset of cognitive impairment and seizures should alert the treating physician to look carefully for PML. Secondly, in cases of SLE where the diagnosis of the cause of cognitive impairment and seizures is not clear, we suggest that immunosuppression should not be intensified until PML has clearly been ruled out. Lastly, multidisciplinary care in patients with suspected neuropsychiatric SLE including a neurologist, an infectious diseases consultant, a neuroradiologist, and a rheumatologist is needed.

Intravascular large B-cell lymphoma affecting multiple cranial nerves: A histopathological study

Intravascular large B‐cell lymphoma (IVLBCL) is a rare form of lymphomas with poor prognosis, characterized by atypical lymphocytes selectively growing within the lumen of small or medium‐sized vessels. Here, we report a case of intracerebral IVLBCL in a 54‐year‐old man who died three months after symptom onset. The diagnosis was made by postmortem pathological examination, based on the identification of multiple ischemic lesions, with small or medium‐sized vessels filled with malignant B‐cells, in the cerebral hemispheres, cerebellum, midbrain, and medulla oblongata, including the external cuneate nucleus and trigeminal spinal tract nucleus. Apart from necrotic lesions, specific histopathological search for occluded vessels in the other brain stem structures permitted identification of significant involvement of the cuneate nucleus, solitary tract nucleus, hypoglossal nucleus, and inferior olivary complex. Small vessels affected by IVLBCL were also found in the trunks of the oculomotor, trigeminal, glossopharyngeal, vagal, and hypoglossal nerves. These histopathological findings were consistent with some cranial nerve symptoms/signs ascertained during hospitalization, such as diplopia, dysphonia, and asymmetry/hypomotility of the palatal veil. The case study presented here reports novel insights on radiological, anatomical, and clinical correlations of the IVLBCL, including the possible involvement of nuclei and trunks of multiple cranial nerves. The reported findings may help clinicians in the early identification of this rapidly progressive disease that can be easily misdiagnosed, through integrated neuroradiological, neurological and neuropathological approaches.