Mycoplasma pneumoniae Carriage With De Novo Macrolide-Resistance and Breakthrough Pneumonia Ammar Saadoon Alishlash, MD,a Thomas Prescott Atkinson, MD, PhD,a Charles Schlappi, MD,a Sixto M. Leal, Jr, MD, PhD,b Ken B. Waites, MD,b Li Xiao, PhDc Mycoplasma pneumoniae pneumonia is prevalent in children and can be abstract followed by upper airway carriage for months. Treatment of M pneumoniae pneumonia with macrolides is widespread and can lead to the development of macrolide resistance. The clinical consequences of Departments of aPediatrics, bPathology, and cMedicine, chronic M pneumoniae carriage are unknown. In this article, we describe University of Alabama at Birmingham, Birmingham, a child with acute lymphoblastic leukemia who developed macrolide- Alabama susceptible M pneumoniae pneumonia confirmed by nasopharyngeal Drs Alishlash, Atkinson, and Schlappi conceptualized, secretions polymerase chain reaction and culture with good response to designed, and analyzed the clinical information of M the case report and drafted the initial manuscript; azithromycin. Five months later, the patient developed another Dr Xiao participated in the concept, design, and pneumoniae pneumonia that was diagnosed with positive macrolide- analysis of the case report, performed the resistant Mpneumoniaepolymerase chain reaction and culture from the laboratory analysis of the case report, and drafted bronchoalveolar lavage. The child responded well to fluoroquinolones and the initial manuscript; Drs Waites and Leal Jr were involved in the design and concept of the case report eventually was discharged from the hospital. The M pneumoniae recovered and critically reviewed the data and manuscript for from the second pneumonia is a novel strain and is genetically identical to important intellectual content; and all authors the M pneumoniae that caused the first pneumonia, apart from the reviewed and revised the manuscript, approved the final manuscript as submitted, and agree to be macrolide-resistance 23S ribosomal RNA gene. Both isolates are identical in accountable for all aspects of the work. both P1 (subtype 2 with a novel variant, 2bv) and multiple-locus variable DOI: https://doi.org/10.1542/peds.2019-1642 number tandem repeat analysis type (53662). This is indicative of chronic M Accepted for publication Jun 28, 2019 pneumoniae carriage with de novo macrolide-resistance mutation and fi Address correspondence to Ammar Saadoon subsequent breakthrough pneumonia that is reported for the rst time here. Alishlash, MD, Department of Pediatrics, University of Children with immunosuppression may be at increased risk of life- Alabama at Birmingham, 1600 7th Ave S, Lowder 620, threatening macrolide-resistant pneumonia after M pneumoniae carriage. Birmingham, AL 35233. E-mail: ammarsaadoon@ uabmc.edu Further studies are required to evaluate the impact of this phenomenon. This will then guide strategies to limit the associated morbidity, such as PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275). testing for macrolide resistance, treatment of M pneumoniae pneumonia in fl Copyright © 2019 by the American Academy of high-risk children with bactericidal antibiotics (such as uoroquinolones), Pediatrics M pneumoniae and possibly eradication protocols of carriage to prevent FINANCIAL DISCLOSURE: The authors have indicated subsequent life-threatening infections. they have no financial relationships relevant to this article to disclose. FUNDING: Supported by US Centers for Disease Control and Prevention contract 200-2017-96217 to Dr Waites. Acute Mycoplasma pneumoniae develop a de novo mutation in the 23S POTENTIAL CONFLICT OF INTEREST: infections result in significant ribosomal RNA (rRNA) gene conferring The authors have indicated they have no potential conflicts of interest 2–5 morbidity in the pediatric population, macrolide resistance. To the authors’ to disclose. with subsequent carriage in the upper knowledge, there are no reported cases airways sometimes for months, even of a recurrence of invasive pulmonary To cite: Alishlash AS, Atkinson TP, Schlappi C, after antibiotic treatment.1 When M infection during the carriage period in et al. Mycoplasma pneumoniae Carriage With De pneumoniae pneumonia is treated humans. In this article, we report M Novo Macrolide-Resistance and Breakthrough Pneumonia. Pediatrics. 2019;144(4):e20191642 with macrolides, the organism may pneumoniae carriage for months with Downloaded from www.aappublications.org/news by guest on September 25, 2021 PEDIATRICS Volume 144, number 4, October 2019:e20191642 CASE REPORT de novo macrolide-resistance mutation and subsequent development of clinically significant M pneumoniae pneumonia in an immunocompromised child. CASE REPORT Our patient is a 3-year-old girl with high-risk pre-B acute lymphoblastic leukemia that was diagnosed in September 2017. In May 2018, the patient was admitted to the Children’s of Alabama hospital because of a fever of 101°F and worsening cough that had been lingering for few weeks in the setting of continued treatment of her acute lymphoblastic leukemia with doxorubicin and vincristine. Respiratory physical examination was normal. Her complete blood count showed neutropenia (absolute neutrophil count of 150/µL). Chest radiograph revealed left lower lobe subsegmental atelectasis. The treating team started her on cefepime and continued her home fluconazole for a previously diagnosed Candida tropicalis osteomyelitis. Nasopharyngeal aspirate tested positive for Mpneumoniaeby using a multiplexed polymerase chain reaction (PCR) test for multiple respiratory pathogens (GenMark Diagnostics). The panel result was negative for 14 viruses and Chlamydia pneumoniae. Nasopharyngeal culture FIGURE 1 later grew Mpneumoniaein the Chest computerized tomography with contrast during the second admission in October 2018 University of Alabama at Birmingham showing alveolar consolidations of (A) the right upper lobe, most confluent in the posterior seg- Diagnostic Mycoplasma Laboratory ment, and (B) the right lower lobe (red arrows) and hilar lymphadenopathy (yellow arrow). It also shows the implanted central venous line at the left side anteriorly. (isolate No. 72749).6 M pneumoniae macrolide resistance real-time PCR assay demonstrated lack of macrolide- associated with a worsening cough both lungs. Over the next 7 days, she resistance mutations in the 23S rRNA that was present for 2 weeks before received cefepime and her home fl gene.7 The minimum inhibitory admission. The family denied any sick uconazole. She continued to suffer concentration (MIC) for erythromycin contacts or family members with high-spiking fevers and a subsequent was 0.004 µg/mL, confirming macrolide similar symptoms. The patient was decline in respiratory status, which susceptibility.8 Accordingly, the child neutropenic (absolute neutrophil included tachypnea and hypoxemia. µ received high-dose azithromycin count 470/ L), and her Chest computed tomography on day 8 (10mg/kgperday)for3dayswith nasopharyngeal aspirate test was of admission revealed right upper subsequent resolution of the fever, positive for rhinovirus and lobe and right lower lobe pneumonia M improvement of the cough, and enterovirus but negative for with right hilar and paratracheal pneumoniae discharge from the hospital. by multiplexed PCR. She lymphadenopathy (Fig 1). had a normal examination of her In October 2018, the patient was lungs. Her chest radiograph showed A repeat nasopharyngeal multiplexed readmitted for a febrile illness scattered interstitial infiltrates in PCR assay was negative for the Downloaded from www.aappublications.org/news by guest on September 25, 2021 2 ALISHLASH et al previously recovered viruses and for testing. Accordingly, azithromycin reference sequences from the M pneumoniae. To uncover the was changed to levofloxacin, with National Center for Biotechnology causative infection, the pulmonary eventual improvement of the fever, Information. Results showed that team obtained bronchoalveolar hypoxemia, and respiratory both strains were P1 subtype 2 with lavage (BAL), which tested positive symptoms. Four days later, the a novel variant (that has not been for M pneumoniae by real-time PCR patient was discharged to complete reported) denoted 2bv that has a 12- and by culture.9 Azithromycin and the antimicrobial course at home. bp deletion (CCAATTCCCAAA) at the vancomycin were then added because RepMP2/3 locus (position 3738, of continued clinical worsening. The Molecular genotyping was performed AP017318.1_ [179335-184254]) following day, a macrolide-resistance on the isolates recovered from the 2 compared with variant 2b. The MLVA mutation in the 23S rRNA gene was admissions in 2 ways: P1 subtyping type of both strains was 53662. Thus, identified in the isolate by M (determining sequence variations in except for the macrolide-resistance pneumoniae macrolide resistance the polymorphic P1 adhesin gene)10 mutation, the genetic fingerprints of real-time PCR assay. Sequencing of and multiple-locus variable number the 2 M pneumoniae organisms the amplicon confirmed 2 different tandem repeat analysis (MLVA) obtained from the 2 clinical point mutations conferring macrolide (which counts the copy number of encounters were novel and identical, resistance in a mixed population naturally varying tandem repeated suggesting the persistence of the (A2063G or A2063T; Escherichia coli DNA sequences found in different loci same strain. numbering 2058) (Fig 2). BAL culture throughout the M pneumoniae grew M pneumoniae with an genome).11 The