Clinical Features, Diagnosis, and Treatment Plans of Balamuthia mandrillaris Encephalitis in Pediatrics: A Systematic Review

Background: Balamuthia mandrillaris is a free-living amoeba responsible for a rare but fatal microbial encephalitis in pediatric patients. Pediatric cases are extremely rare and typically present with nonspecific symptoms, leading to delayed diagnosis and poor outcomes.  Objectives: The aim of this study was to systematically review reported pediatric cases of Balamuthia-induced encephalitis to better characterize clinical manifestations, diagnostic approaches, treatment strategies, and patient outcomes.  Methods: This study was conducted based on the PRISMA flow diagram. Papers reporting B. mandrillaris encephalitis in pediatrics were identified through searching in international databases, including MEDLINE/PubMed, Scopus, Web of Science, and Science Direct, and the Google Scholar search engine up to July ۲۰۲۳. Inclusion criteria were English-language case reports or case series involving patients under ۱۸ years of age with confirmed Balamuthia encephalitis. The collected studies were screened based on the inclusion and exclusion criteria. The review protocol was registered in PROSPERO. The quality of included articles was assessed using JBI critical appraisal tools for case reports.  Results: Thirty-four articles met the inclusion criteria, reporting ۵۷ infected children. Patients ranged in age from ۸ months to ۱۸ years, with a mean age of ۷.۸ years. Only four children could survive (۷%). The most common clinical manifestations were fever, headache, and loss of consciousness. There was a lack of specificity in cerebrospinal fluid, computed tomography (CT) scan, and magnetic resonance imaging (MRI) findings, which made it hard to diagnose. MRI was performed in ۴۵ patients, and all of them showed abnormalities, such as multiple lesions. The most common diagnostic method was ​polymerase chain reaction (PCR) on cerebrospinal fluid, brain tissue, or skin lesion; however, next-generation sequencing (NGS) appeared to be a more efficient and faster alternative. Multiple-drug therapy was used in the surviving cases.  Conclusions: Although B. mandrillaris encephalitis is rare, it might become a health concern in the future due to its extremely high mortality rate. Healthcare providers should be informed about the clinical manifestations, appropriate diagnostic tools, and possible treatments of this potentially life-threatening microbial encephalitis. Early diagnosis and rapid intervention may improve the chance of survival.

کلیدواژه ها:

Balamuthia mandrillaris ، Encephalitis ، Pediatrics ، Infectious disease ، Systematic review