Long-term prognosis and overall mortality in patients with progressive multifocal leukoencephalopathy

Mixed nontuberculous mycobacteria in an immunocompromised patient with probable progressive multifocal leukoencephalopathy

Objectives

Nontuberculous mycobacteria (NTM) are increasingly recognized opportunistic pathogens found ubiquitously in the environment. The presence of multiple NTM species at the site of disease complicates diagnosis and treatment.

Case and management

A 40-year-old patient who tested positive for HIV, with an absolute clusters of differentiation 4+ T-cell count of 3 cells/µl and cryptococcaemia, presented with hemoptysis, productive cough, and weight loss. Mixed NTM species, including Mycobacterium kansasii and Mycobacterium chelonae, were detected by the GenoType Mycobacterium Common Mycobacteria line probe assay from respiratory specimens, with Mycobacterium avium bacteremia also identified in the same month. An empirical regimen of azithromycin, ethambutol, isoniazid, and rifabutin was initiated to address recurrent positive cultures with M. kansasii and the NTM bacteremia. Despite this treatment, the patient experienced neurologic deterioration, was diagnosed with probable progressive multifocal leukoencephalopathy, and subsequently died.

Additional investigation

Advanced diagnostic techniques, including Sanger sequencing, Deeplex Myc-TB in combination with short-read next-generation sequencing, and targeted amplicon-based Oxford Nanopore Technologies long-read sequencing, revealed the presence of mixed NTM species in two retrospective stored cultures, with variations in primer binding affinity among the M. kansasii and M. avium.

Conclusion

This case highlights the individualized considerations required to manage a patient with mixed NTM infection and the need for multi-target diagnostic approaches.

MRI Shrimp Sign and Parietooccipital Lesion in Progressive Multifocal Leukoencephalopathy

Recognizing the MRI characteristics of progressive multifocal leukoencephalopathy is essential for early diagnosis. This report describes the oldest known case of an 83-year-old man with rapidly progressive dementia and HIV-associated classic PML. Brain MRI revealed hallmark findings, including asymmetric, continuous, non-enhancing subcortical lesions in the parietooccipital regions and the "shrimp sign" in the cerebellar white matter. These characteristic imaging patterns, in the appropriate clinical context, are clues for the early identification of PML.

Progressive multifocal leukoencephalopathy and spectrum of predisposing conditions: a 20-year retrospective cohort study in a tertiary center in São Paulo, Brazil

BACKGROUND

Epidemiological studies on predisposing conditions and outcomes of progressive multifocal leukoencephalopathy (PML) cases have been carried out exclusively in high-income countries. We aim to report and compare the main characteristics and outcomes of patients with PML and several underlying diseases in a referral center in a middle-income country.

METHODS

We performed a retrospective cohort study of PML cases admitted to a tertiary care hospital in São Paulo, Brazil during 2000-2022. Demographic and PML-specific variables were recorded. One-year case-fatality rate and factors associated with death were identified using a multivariate Cox proportional hazards regression model.

RESULTS

Ninety-nine patients with PML were included. HIV infection (84.8%) and malignancy (14.1%) were the most prevalent underlying conditions. Other predisposing diseases were autoimmune/inflammatory diseases (5.1%) and solid organ transplantation (1.0%). One (1.0%) patient had liver cirrhosis and another (1.0%) patient was previously healthy. Focal motor deficits (64.2%) and gait instability (55.1%) were the most common signs. The one-year case-fatality rate was 52.5% (95% CI 42.2-62.7). The one-year case-fatality rate (95% CI) in patients with or without malignancy (85.7%, 95% CI 57.2-98.2% and 47.1%, 95% CI 36.1-58.2%, respectively) were statistically different (P = 0.009). Crude and adjusted Cox regression models identified malignancy as independently associated with death (adjusted HR = 3.92, 95% CI 1.76-8.73, P = 0.001).

CONCLUSIONS

HIV/AIDS was the predisposing condition in 84.8% of PML cases. The one-year case-fatality rate was 52.5% and having a malignancy was independently associated with death. This study reports emerging data on the epidemiology and outcome of PML in a middle-income country.

Integrins as Drug Targets in Vascular and Related Diseases

Integrins are transmembrane receptors that, as critical participants in a vast range of pathological processes, are potential therapeutic targets. However, in only a few cases has the promise been realized by drug approval. In this review, we briefly review basic integrin biology and participation in disease, challenges in the development of safe, effective integrin-targeted therapies, and recent advances that may lead to progress.