Diffei Academic丨mNGS rapidly diagnoses rare central and blood dual system mixed infections

Introduction

Recently, Professor Xu Tianmin’s team from the Department of Infectious Diseases of Changzhou Third People’s Hospital cooperated with Difei Medical to conduct aBMC Infectious Diseases(IF=3.7)The magazine published a rare case report,The patient's central nervous system and blood system are co-infected with hepatitis E virus (HEV) and Klebsiella pneumoniae. The advantages of mNGS in the diagnosis of mixed infections are highlighted.。

Research Background

HEVIt is the main cause of acute viral hepatitis around the world (especially in developing countries). In rare cases, it can also enter the cerebrospinal fluid and cause central nervous system infection.Klebsiella pneumoniae, as a common nosocomial infection pathogen, is susceptible to infecting immunocompromised people.To date, no cases of co-infection with HEV and Klebsiella pneumoniae have been reported.

In this case, the patient hasHEVCo-infection of the central nervous system and blood system with Klebsiella pneumoniae, with an acute onset and rapid progression.With the help of timely and accurate detection by mNGS, the patient improved and was discharged after targeted clinical treatment.

Case presentation

Local hospital diagnosis and treatment process

The patient was a 68-year-old male with a 40-year history of bronchiectasis. He had taken ciprofloxacin and amoxicillin many times to treat infections secondary to bronchiectasis.On April 5, 2023, he went to the local Jintan People's Hospital due to 'sudden fever, headache, and slightly stiff neck.' The biochemical indicators alanine aminotransferase and aspartate aminotransferase were significantly elevated, indicating abnormal liver function.Brain MRI showed senile brain changes and bilateral sphenoid sinusitis.Blood cultures were performed at the local hospital.

Diagnosis and treatment process of Changzhou Third Hospital

Admission diagnosis and treatment

2023On April 7, 2018, the patient was transferred to Changzhou Third People's Hospital, where he was initially diagnosed with central nervous system infection and liver dysfunction.After admission, the highest body temperature reached 40°C, severe headache, and yellow watery diarrhea.Inflammatory indicators such as WBC, PCT, CRP and II-6 were significantly increased.

After admission, magnesium isoglycoside oxalate injection (150 mg qd) and polyene phosphatidylcholine injection (697.5 mg qd) were given for hepatoprotective treatment, and mannitol (150 ml q6h) and glycerofructose (150 ml q12h) were given to reduce intracranial hepatotoxicity. For pressure, linezolid glucose (0.6g q12h) and meropenem injection (2g q8h) were given for empiric anti-infective treatment, dexamethasone injection 5mg qd was given for anti-inflammatory treatment for 7 days, and Saccharomyces boulardii powder (0.5g) was taken orally. bid) regulates intestinal flora.

Further examination and treatment

4On March 8, a lumbar puncture was performed to collect cerebrospinal fluid.The appearance of the cerebrospinal fluid was light yellow, and routine testing showed an increase in WBC count, mainly multinucleated cells, an increase in protein, and a decrease in glucose and chloride, suggesting central nervous system infection and suspected purulent meningitis.At the same time, the hepatitis E virus IgM was 8.086 S/co, indicating hepatitis E.Cerebrospinal fluid and blood samples were further sent for culture and mNGS testing.

4On the 9th of the month,mNGSThe results reported that HEV and Klebsiella pneumoniae were detected in cerebrospinal fluid and blood samples..At the same time, the quantitative results of HEV RNA showed that the content in blood was 1.8E+04copy/ml and the content in feces was 8.4E+03copy/ml.Linezolid was discontinued and meropenem was continued to be injected to fight infection.On April 19, the blood culture result from the local hospital reported positive for Klebsiella pneumoniae, and the drug susceptibility indicated that only ampicillin was resistant, so the antibiotics were adjusted and downgraded to ceftazidime injection.

Figure 1 Genome coverage of Klebsiella pneumoniae and HEV in cerebrospinal fluid samples

Outcome and Prognosis

After treatment, the patient's body temperature returned to normal, headaches were alleviated, inflammation indicators gradually declined during reexamination, and liver function improved.

4On March 18, lumbar puncture was performed again, and the appearance of the cerebrospinal fluid was colorless and clear, and the inflammatory indicators dropped.

4On March 19, HEV RNA quantification of blood and stool samples was rechecked, and the results were negative.

4On March 26, the patient improved and was discharged.

Summarize

1. This case is the first to report a rare case of co-infection of the central nervous system and blood system with HEV and Klebsiella pneumoniae.

2.HEVSevere impairment of liver function caused by infection may cause HEV and other opportunistic pathogens to penetrate the blood-brain barrier and cause severe central nervous system infection.

3. Central nervous system infections generally have an acute onset and rapid progression.In this mixed infection case, mNGS demonstrated its characteristics of unbiased, wide coverage, and high timeliness.

references:

Cui M, Sun W, Xue Y, Yang J, Xu T. Hepatitis E virus and Klebsiella pneumoniae co-infection detected by metagenomics next-generation sequencing in a patient with central nervous system and bloodstream Infection: a case report. BMC Infect Dis. 2024 Jan 2;24(1):33. doi: 10.1186/s12879-023-08850-4. PMID: 38166638; PMCID: PMC10763291.

Author: Xiaoyang Reviewer: Jia, Shannai Typesetting: Lin