Mycoplasma hominis Meningitis in a 24 Week Premature Neonate: Case Report and Short Literature Review

[Moxifloxacin treatment for Mycoplasma hominis meningitis in an extremely preterm infant]

The patient, a male newborn, was admitted to the hospital 2 hours after birth due to prematurity (gestational age 27+5 weeks) and respiratory distress occurring 2 hours postnatally. After admission, the infant developed fever and elevated C-reactive protein levels. On the fourth day after birth, metagenomic next-generation sequencing of cerebrospinal fluid indicated a positive result for Mycoplasma hominis (9 898 reads). On the eighth day, a retest of cerebrospinal fluid metagenomics confirmed Mycoplasma hominis (56 806 reads). The diagnosis of purulent meningitis caused by Mycoplasma hominis was established, and the antibiotic treatment was switched to moxifloxacin [5 mg/(kg·day)] administered intravenously for a total of 4 weeks. After treatment, the patient's cerebrospinal fluid tests returned to normal, and he was discharged as cured on the 76th day after birth. This article focuses on the diagnosis and treatment of neonatal Mycoplasma hominis purulent meningitis, introducing the multidisciplinary diagnosis and treatment of the condition in extremely preterm infants.

A Case Report of Mycoplasma hominis Subdural Empyema Following Decompressive Craniotomy, and a Review of Central Nervous System Mycoplasma hominis Infections

Background

Mycoplasma hominis is a small cell-wall-free organism, part of the normal microbiota of the genitourinary tract. It is rarely involved in extragenital infections, mainly joint, surgical-site, and respiratory infections.

Methods

We describe a case of M. hominis subdural empyema and lower limb surgical site infections, following decompressive craniotomy, after traumatic brain and extremities injury. In addition, a literature review of 34 cases M. hominis CNS infections was done.

Results

Our case depicts a 25-years old patient who developed subdural empyema and surgical site infections in his cranium and fibula. Both sites were cultured, and small pinpoint colonies grew on blood agar. MALDI-TOF MS identified M. hominis. Simultaneously 16S-rDNA PCR from CSF detected M. hominis. Antimicrobial treatment was switched to doxycycline with improvement. Literature review revealed 21 adults and 13 pediatric cases of M. hominis CNS infection. Risk factors in adults were head trauma, neurosurgery, or post-partum period.

Conclusions

Based upon the literature reviewed, we postulate that adult patients with head trauma or neurosurgical procedure, rarely are infected either through direct contamination during the trauma, or by undergoing urgent, urinary catheterization, and may experience distant infection due to translocation of M. hominis into the bloodstream. In such cases diagnosis is delayed due to difficulties in growing and identifying the bacteria. Empiric antimicrobials are usually not effective against mycoplasmas. These factors contributed to the mortality in adult cases (15%). Our rare case highlights the necessity of combining classical microbiology routines with advanced molecular techniques to establish a diagnosis in complicated cases.

Therapeutic Drug Monitoring of Moxifloxacin to Guide Treatment of Mycoplasma hominis Meningitis in an Extremely Preterm Infant

Mycoplasma hominis (M hominis) is a rare cause of neonatal bacterial meningitis. Treatment can be challenging because of M hominis' intrinsic antibiotic resistance and the difficulty in accessing antimicrobial susceptibility testing. In this report, we describe an extremely preterm male infant with seizures who had a subsequent diagnosis of M hominis meningitis. Because of severity of illness, doxycycline (4 mg/kg IV every 24 hours) and moxifloxacin (5 mg/kg IV every 24 hours) were started empirically. Repeat cerebrospinal fluid cultures were negative and showed decreasing pleiocytosis. Given the concentration-dependent killing of moxifloxacin and concern for endovascular infection from a concomitant cerebral venous sinus thrombosis, serum concentrations of moxifloxacin were obtained to estimate pharmacokinetic and pharmacodynamic parameters. These were compared to the targets described in other case reports of M hominis meningitis. The maximum serum concentration (C_max) was 2.5 mg/L, volume of distribution was 2.2 L/kg, clearance was 0.18 L/kg/hr, terminal half-life was 8.6 hours, and area-under-the-concentration-time curve (AUC) was 28.1 mg•hr/L. Using the range of minimum inhibitory concentrations (MICs) reported in the literature, the estimated C_max/MIC for this patient was 21 to 158 (target C_max/MIC: >10) and AUC/MIC was 234 to 1757 (target AUC/MIC: ≥100). Doxycycline and moxifloxacin were continued for 6 weeks. No adverse events to moxifloxacin or doxycycline were observed in the NICU. This report describes the successful treatment of M hominis neonatal meningitis and adds to the knowledge of pharmacokinetic and pharmacodynamic parameters of moxifloxacin in neonates. Additional data will help to confirm the role for routine therapeutic drug monitoring of moxifloxacin in neonates.

Mycoplasma hominis meningitis in an extremely preterm newborn: a case report

Background

Mycoplasma Hominis is a micro-organism which is a part of the human genitourinary tract flora. Neonates are susceptible to acquire this pathogen either in utero or through vertical transmission. In rare cases, it may cause central nervous system infections with severe morbidity and mortality in preterm and term neonates.

Case presentation

We present a case of Mycoplasma Hominis meningitis in an extremely preterm neonate who presented with lethargy, tachycardia and seizures on day 7 of life. There was no history of maternal systemic or genitourinary infection during pregnancy and at the time of delivery. Empirical antibiotic therapy for neonatal meningitis was commenced after sending blood and cerebrospinal fluid cultures. Cerebrospinal fluid analysis showed pleocytosis with neutrophilic predominance, but no bacteria was identified on gram staining. Blood culture yielded no growth of any bacterial pathogen. However, growth of Mycoplasma Hominis was suspected in cerebrospinal fluid culture which was confirmed by 16S ribosomal ribonucleic acid (RNA) polymerase chain reaction analysis. Subsequently, antibiotics were changed to Moxifloxacin and Doxycycline which were given for a total duration of 6 weeks. Multiple cerebrospinal fluid cultures were performed during this treatment. No growth of any pathogen was identified on any of these cerebrospinal fluid cultures.

Conclusions

We report a rare case of Mycoplasma Hominis meningitis in an extremely preterm neonate which was successfully treated with a combination therapy of Moxifloxacin and Doxycycline.

It is important to consider the possibility of Mycoplasma Hominis meningitis in neonates who present with clinical signs and pleocytosis in cerebrospinal fluid but negative gram staining and no growth on conventional culture media.