Dados do Trabalho

Título

IS HUMAN HERPESVIRUSES 6/7 DETECTION ALWAYS PATHOLOGICAL?

Apresentação do caso

Case A: 14-year-old female, history of headache, fever, and respiratory symptoms. COVID-19 positive through antigen-based testing. Symptoms persisted for 1 week, when the patient presented with intense headache, vomiting, and drowsiness. Upon evaluation in the emergency room, neck stiffness was noted, and ceftriaxone was initiated. Cerebrospinal fluid (CSF) showed a cell count of 1275/mm³ with predominance of neutrophils, glucose of 30 mg/dL, and protein level of 101 mg/dL. Peripheral blood culture was positive for Streptococcus constellatus. The patient developed subdural empyema and the culture of its drainage confirmed the same pathogen. Viral panel examination revealed a positive PCR result for Human herpesviruses 6/7 (HHV-6/7).

Case B: 8-year-old male, history of irritability associated with ptosis of the right eyelid and altered extrinsic and intrinsic ocular motility of the same eye at around 1 year of age. Brain MRI showed hyperintense right III cranial nerve, and CSF analysis showed no cytological or biochemical changes. Pulse therapy for 5 days was performed, resulting in complete resolution. Subsequently, the CSF PCR test revealed a positive result for HHV-6/7. In the follow-up, the patient was diagnosed with recurrent painful ophthalmoplegic neuropathy, later characterized as associated with episodes of headache. At 5 years old, a repeat CSF examination showed a positive PCR result for HHV-6/7.

Case C: 14-year-old male presented with bilateral visual impairment associated with bilateral ocular pain, worse on the right side, without signs of ocular redness. After 4 days, bilateral amaurosis developed. Investigation with CT angiography of the skull and brain MRI showed no abnormalities. CSF analysis showed no cytological or biochemical changes but a positive PCR result for HHV-6/7.

Discussão

We present here three cases in which the clinical relevance of HHV-6/7 detection in the CSF is questioned. There is a significant genetic similarity between these two viruses. Both have the ability to cause latency, asymptomatic reactivation, and, in the case of HHV-6, it can be integrated into chromosomal DNA. Therefore, results should be analyzed with caution to not misinterpret a positive HHV-6/7 test.

Comentários finais

CSF detection of HHV6/7 is not always pathognomonic of an infection to be treated.

Referências (se houver)

Bharucha T, Houlihan CF, Breuer J. Herpesvirus Infections of the Central Nervous System. Semin Neurol. 2019 Jun;39(3):369-382. doi: 10.1055/s-0039-1687837. Epub 2019 Aug 2. PMID: 31378872.

Clark DA. Clinical and laboratory features of human herpesvirus 6 chromosomal integration. Clin Microbiol Infect. 2016 Apr;22(4):333-339. doi: 10.1016/j.cmi.2015.12.022. Epub 2016 Jan 21. PMID: 26802216.

Pandey U, Greninger AL, Levin GR, Jerome KR, Anand VC, Dien Bard J. Pathogen or Bystander: Clinical Significance of Detecting Human Herpesvirus 6 in Pediatric Cerebrospinal Fluid. J Clin Microbiol. 2020 Apr 23;58(5):e00313-20. doi: 10.1128/JCM.00313-20. PMID: 32102858; PMCID: PMC7180253.

Kharbat AF, Lakshmi-Narasimhan M, Bhaskaran S, Parat S. Incidental Detection of Human Herpesvirus-6 in Cerebrospinal Fluid Analysis: To Treat or Not to Treat? Cureus. 2022 Jun 3;14(6):e25629. doi: 10.7759/cureus.25629. PMID: 35785001; PMCID: PMC9249039.

Palavras Chave

human herpesvirus-6 (hhv-6), human herpesvirus-7 (hhv-7), pediatric

Declaração de conflito de interesses de TODOS os autores

Não há conflitos de interesse