Picornaviruses in cerebrospinal fluid of children with meningitis in Luanda, Angola

Sudden Infant Death Associated with Rhinovirus Infection

A less than one-month-old infant with symptoms of rhinitis died unexpectedly in his sleep. He was not born prematurely and had no known underlying disease. Cerebrospinal fluid, nasopharyngeal and lung samples, and rectal swab were found to be positive for subgroup A rhinovirus, while the blood was negative. This case highlights the important finding that the rhinovirus, a common pathogen associated with upper respiratory tract infections, can sometimes, as the only pathogen, lead to complications such as a cerebrospinal infection and be involved in the sudden infant death syndrome (SIDS). Vigilance is necessary in case of viral infections in the infant's environment, and measures of hygiene and protection must be encouraged in order to reduce the risk of the SIDS.

Metagenomic search of viral coinfections in herpes simplex encephalitis patients

Little is known about concomitant central nervous system (CNS) infections by more than one virus. Current diagnostics are based on molecular tests for particular pathogens making it difficult to identify multi-viral infections. In the present study, we applied DNA- and RNA-based next-generation sequencing metagenomics (mNGS) to detect viruses in cerebrospinal fluids from 20 patients with herpes simplex encephalitis. Coinfection was detected in one patient: sequences in cerebrospinal fluids matched enterovirus A (2.660 reads; 4% of recovered genome) and enterovirus B (1.571 reads; 13% of recovered genome). Subsequent PCR combined with serotyping allowed to identify human echovirus 6, a representative of enterovirus B. Several other mNGS hits (human pegivirus, Merkel cell polyomavirus, human papillomavirus type 5) were not considered to represent a genuine signal as they could not be confirmed by specific RT-PCR/PCR. HSV DNA, while being detectable by PCR in every patient, was detected by mNGS in only one. In conclusion, contaminations and false signals may complicate mNGS interpretation; however, the method can be useful in diagnostics of viral coinfections in CNS, particularly in the case of rare pathogens.

A severe case of human rhinovirus A45 with central nervous system involvement and viral sepsis

Background

Rhinovirus is a common viral aetiology of upper respiratory infection and is mostly associated with common cold or flu-like illness. Although rhinovirus has been recognized as a pathogen for lower respiratory infections in severe cases credited to advances in molecular detection, central nervous system involvement and multiorgan dysfunction are extremely rare.

Case presentation

A previously healthy 10-year-old girl developed fever, sore throat and conjunctive injection after contact with an upper respiratory infection patient, followed by seizures, haematuria, and severe diarrhoea. She experienced viral sepsis and multiorgan dysfunction after admission. Cerebral computed tomography showed significant diffuse encephaledema. Cerebrospinal fluid analysis showed significantly elevated protein levels. After her consciousness disturbance improved, she still took a long time to recover from haematuria and diarrhoea. We identified a rarely reported rhinovirus A45 in her oropharyngeal and anal swabs by metagenomic next-generation sequencing, and bacterial culture of blood specimens yielded negative results.

Conclusions

This case presents a patient with severe rhinovirus infection, which was very likely responsible for her central nervous system symptoms and viral sepsis.

Viral Etiologies of Meningitis in Patients with Presumed Pyogenic Meningitis at University Hospitals in Ethiopia

Introduction

Viral meningitis is common in most resource-limited settings, posing a challenge for the management and prognosis of suspected patients. No study has been done on the detection of either viral or viral-bacterial co-infection among presumed pyogenic meningitis cases in Ethiopia. We, therefore, aimed to determine the distribution of cytomegalovirus (CMV) and human enteroviruses (HEVs) among patients with presumptive pyogenic meningitis at University hospitals in Ethiopia.

Methods

Viral nucleic acid was extracted from 86 repository CSF samples, which were collected from patients presumptively diagnosed with pyogenic meningitis between 2012 and 2013. PCR was done consecutively to investigate the possible viral etiologic agents of meningitis.

Results

HEVs were detected in 11 (12.8%) of the analyzed samples while none of the 86 samples were tested positive for CMV. Viral-bacterial co-infections were found among 4/11 (36.4%) confirmed cases. The majority of the patients (10/11) with HEVs were younger aged ≤ 19 years old.

Conclusions

In this study, the magnitude of HEVs was shown to have a significant role in presumed pyogenic meningitis cases. Therefore, we recommend presumed pyogenic meningitis cases to be inspected for viral etiologies and improve meningeal symptoms interpretations.

Clinically Mild Encephalitis/Encephalopathy with a Reversible Splenial Lesion Associated with Rhinovirus

A 2-year-old girl with fever and seizures was diagnosed as having clinically mild encephalitis/encephalopathy with a reversible splenial lesion, as indicated by magnetic resonance imaging. Virologic analysis identified human rhinovirus A49 in her serum. Although human rhinovirus rarely involves the central nervous system, such involvement could result in mild encephalitis/encephalopathy with a reversible splenial lesion.

Microglia HMC3 cells are highly susceptible to Rhinovirus infection

Human rhinovirus (HRV) affects the lower and upper respiratory tract, however, some studies suggest that HRV infection can lead to extrapulmonary complications in critical illness. Moreover, some reports have shown the presence of HRV in patients with Central Nervous System (CNS) disease. During a CNS infection, the microglia cells are the first line of defense against pathogens. In this study, the susceptibility of the human microglial clone 3 cell line (HMC3) to HRV infection was analyzed. Our findings demonstrate for the first time that HRV is capable of completing the entire viral cycle in microglial cells.

Rhinovirus-associated acute encephalitis/encephalopathy and cerebellitis

BACKGROUND

Rhinovirus is a common respiratory pathogen for children throughout the year; nevertheless, its central nervous system involvement is extremely rare, and only two cases have been reported to date: meningitis and sepsis-like illness.

PATIENT

A previously healthy 2-year-old Japanese boy developed fever, followed by seizures and lethargy. His cerebrospinal fluid cell count and protein level were slightly increased; brain magnetic resonance imaging showed abnormal intensities in the bilateral cerebellar dentate nuclei, which were prominent in diffusion-weighted images. After his consciousness disturbance improved, cerebellar dysfunction became apparent. He was treated symptomatically, without steroids or any other immunosuppressants. He almost recovered within a few months; however, cerebellar atrophy became evident on brain magnetic resonance imaging. Using acute specimens, human rhinovirus A was detected in his throat swab and cerebrospinal fluid.

DISCUSSION

Acute cerebellitis, in which cerebellar inflammation is predominant, is occasionally accompanied by cerebral symptoms, such as consciousness disturbance and seizures. As a causative pathogen, rotavirus is the most common; however, rhinovirus-associated acute encephalitis/encephalopathy and concurrent cerebellitis have not been reported before. Further research, using recent molecular techniques to detect various central nervous system pathogens, including rhinovirus, is needed to delineate the underlying pathophysiology.

Pulmonary and extrapulmonary complications of human rhinovirus infection in critically ill patients

BACKGROUND

Human rhinovirus (HRV) is frequently detected in patients with respiratory tract infection. However, the full clinical spectrum of HRV infection in critically ill patients is not well characterized.

OBJECTIVE

To evaluate the clinical and virological characteristics of critically ill patients with HRV infection.

STUDY DESIGN

HRV-specific reverse transcription-polymerase chain reaction (RT-PCR) was performed on nasopharyngeal aspirate (NPA) specimens from 294 adult patients who required admission into the intensive care unit (ICU). Clinical characteristics were analyzed. HRV genotyping using the 5'UTR-VP4-VP2 region was performed.

RESULTS

HRV was detected in NPA specimens of 22 patients (7.5%) by RT-PCR. Dyspnea was the most common presenting symptom (16/22; 72.7%), but seizure also occurred in 5 (22.7%) patients. Exacerbation of underlying disease occurred in 12 (54.5%) patients. Four (18.2%) patients died, and HRV was considered to play a role as the cause of death in 3 patients. Thirteen (59.1%) patients had pneumonia, and the most common radiological finding was consolidation (6/13; 46.2%). Streptococcus pneumoniae was the most common co-pathogen among patients with pneumonia. Among the 9 patients without pneumonia, 3 patients had exacerbation of underlying lung diseases, 3 patients had acute pulmonary edema, 2 patients with diabetes mellitus had acute complications from poor glycemic control, and 1 patient had status epilepticus. HRV-A was the most common species (64.3%), but there was no clear relationship between HRV species and clinical presentation.

CONCLUSION

Both pulmonary and extrapulmonary complications of HRV were common in critically ill patients.

Viral CNS infections in children from a malaria-endemic area of Malawi: a prospective cohort study

Background

Fever with reduced consciousness is an important cause of hospital admission of children in sub-Saharan Africa, with high mortality. Cerebral malaria, diagnosed when acute Plasmodium falciparum infection and coma are recorded with no other apparent reason, is one important cause. We investigated whether viruses could also be an important cause of CNS infection in such patients, and examined the relative contribution of viral pathogens and malaria parasitaemia.

Methods

We did a prospective cohort study in Blantyre, Malawi. From March 1, 2002, to Aug 31, 2004, we enrolled children aged between 2 months and 15 years who were admitted to hospital with suspected non-bacterial CNS infections. Children with a cerebrospinal fluid (CSF) white cell count of less than 1000 cells per μL and negative bacterial microscopy and culture were deemed to have suspected viral CNS infection. Blood was examined for asexual forms of P falciparum. PCR was done on CSF or on post-mortem brain biopsy specimens to detect 15 viruses known to cause CNS infection.

Findings

Full outcome data were available for 513 children with suspected viral CNS infection, of whom 94 (18%) died. 163 children (32%) had P falciparum parasitaemia, of whom 34 (21%) died. At least one virus was detected in the CNS in 133 children (26%), of whom 43 (33%) died. 12 different viruses were detected; adenovirus was the most common, affecting 42 children; mumps, human herpes virus 6, rabies, cytomegalovirus, herpes simplex virus 1, and enterovirus were also important. 45 (9%) of the 513 children had both parasitaemia and viral infection, including 27 (35%) of 78 diagnosed clinically with cerebral malaria. Children with dual infection were more likely to have seizures than were those with parasitaemia alone, viral infection only, or neither (p<0·0001). 17 (38%) of the 45 children with dual infection died, compared with 26 (30%) of 88 with viral infection only, 17 (14%) of 118 with parasitaemia only, and 34 (13%) of 262 with neither (p<0·0001). Logistic regression showed children with a viral CNS infection had a significantly higher mortality than did those who did not have a viral CNS infection (p=0·001).

Interpretation

Viral CNS infections are an important cause of hospital admission and death in children in Malawi, including in children whose coma might be attributed solely to cerebral malaria. Interaction between viral infection and parasitaemia could increase disease severity.

Funding

Wellcome Trust, US National Institutes of Health, and UK Medical Research Council.

Viral pathogens in children hospitalized with features of central nervous system infection in a malaria-endemic region of Papua New Guinea

BACKGROUND

Viral central nervous system (CNS) infections are common in countries where malaria is endemic but, due to limited laboratory facilities, few studies have systematically examined the prevalence and clinical consequences of the presence of viruses in cerebrospinal fluid (CSF) from children with suspected CNS infection.

METHODS

We performed a prospective study of Papua New Guinean children hospitalized with signs and symptoms of CNS infection. CSF samples from 300 children without proven bacterial/fungal meningitis were analyzed for human herpes viruses (HHV), picornaviruses, influenza, adenoviruses, flaviviruses and bacteria.

RESULTS

Fifty-five children (18%) had viral (42), bacterial (20) or both viral and bacterial (7) nucleic acids (NA) identified in their CSF. Human herpes viruses accounted for 91% of all viruses found. The identification of viral or bacterial NA was not associated with any characteristic clinical features. By contrast, malaria was associated with increased identification of viral and bacterial NA and with impaired consciousness, multiple convulsions and age. Malaria was also inversely associated with an adverse outcome. Amongst children with HHV infection, those with HHV-6 and -7 were younger, were more likely have impaired consciousness and had a higher proportion of adverse outcomes than children with CMV. Dengue and enteroviral infections were infrequent. Adenoviral and influenza infections were not identified.

CONCLUSION

Infections with HHV-6, HHV-7, dengue and enterovirus have the potential to cause serious CNS disease in young PNG children. However most HHVs in this malaria-endemic setting should be considered to be the result of reactivation from a latent reservoir without clinical sequelae.

Fluctuation in hearing thresholds during recovery from childhood bacterial meningitis

BACKGROUND

Hearing loss from childhood bacterial meningitis is believed to develop early and have little tendency for recovery. We performed serial hearing evaluations in a large number of children with bacterial meningitis in Luanda, Angola to clarify if, and how often, the result changed.

METHODS

Children with confirmed bacterial meningitis and hearing evaluations on admission, day 7 of treatment and the follow-up visit formed the study group. Hearing was tested by auditory brainstem response audiometry using stimuli of 40 dB, 60 dB and 80 dB. Threshold changes are described between the composite levels of 40/60 dB and 80/>80 dB.

RESULTS

In all, 235 ears were tested. While the ≤ 60 dB and ≥ 80 dB levels were maintained through all 3 examinations in 54% and 5% of ears, respectively, changes occurred in 41%. Deterioration from the ≤ 60 dB level to ≥ 80 dB was found in 10% of the ears transiently and in 7% permanently. Improvement from the ≥ 80 dB level to ≤ 60 dB occurred in 22% of the ears. Half of the ears with ≥ 80 dB impairment at the follow-up visit arrived with this finding; the others lost hearing later. Maintaining the ≤ 60 dB level throughout was associated with milder disease (P = 0.003), fewer convulsions (P < 0.0001) and older age (P = 0.009).

CONCLUSIONS

Almost half of the ears showed threshold changes after admission during recovery from bacterial meningitis, most frequently improvement of initially severely impaired hearing, but some normal ears or with moderate impairment became severely impaired.

Implementation of the Cepheid Xpert EV assay for rapid detection of enteroviral meningitis: experience of a tertiary care center and a technical review

AIMS

Rapid molecular detection of enterovirus in cerebrospinal fluid (CSF) has revolutionized the diagnosis and treatment modalities of patients with meningitis and largely affected cost of unnecessary antibiotic use and length of stay in hospitals.

MATERIALS AND METHODS

Between January 2010 and July 2012, we tested 220 CSF samples on the GeneXpert DX real-time polymerase chain reaction system (by Cepheid) using the Xpert EV kit assays. In addition, we reported 14 sample results cross-validated with an external referral laboratory as well as the results of external proficiency testing.

RESULTS

Out of all tested samples, 19% were positive for enterovirus. Furthermore, all referred and proficiency testing specimens were concordant with the peer-reviewed and tested samples.

CONCLUSION

Implementation of the Cepheid Xpert EV assay for rapid detection of enteroviral meningitis has been successful in our laboratory. This molecular diagnostic test is currently utilized by our staff physicians as a major tool in assessment and management of patients with meningitis.