Cutaneous Mycobacterium llatzerense Infection in an Immunocompetent Child

To the Editors: Nontuberculosis mycobacteria are found ubiquitously in the environment. With the evolution of molecular typing, the number of mycobacterial species reported has increased to over 190.1 Reported incidence of the disease has been increasing worldwide.2 We present a case of cutaneous Mycobacterium llatzerense in an immunocompetent pediatric patient. A 9-year-old Caucasian Irish boy was referred to the pediatric plastic surgery department with a 7-month history of a gradually increasing lesion on his right cheek. He had no history of fever, night sweats, or weight loss, and no known tuberculosis exposures. He had never received BCG vaccination. His medical history was otherwise unremarkable. Examination demonstrated an easily palpable 1.3 cm × 0.7 cm nontender nodule on the right cheek with overlying violaceous discoloration of the skin (Fig. 1A).FIGURE 1.: (A) Lesion on the right cheek at presentation. (B) There was a reduction in the size of the lesion following punch biopsy and 3 months of antimicrobial therapy.Histologic examination of a skin biopsy (Figure, Supplemental Digital Content 1, https://links.lww.com/INF/F818) showed normal skin overlying necrotizing granulomatous inflammation. Pan-bacterial 16S rRNA polymerase chain reaction on the skin biopsy was positive for M. llatzerense. No sample was available for culture. Detailed laboratory evaluation (Table, Supplemental Digital Content 2, https://links.lww.com/INF/F819) did not reveal any evidence of an inborn error of immunity. An interferon-gamma release assay (Quantiferon) demonstrated no evidence of latent tuberculosis infection, and serology was negative for HIV. Management options were carefully discussed with the child’s parents. Parents opted for the antimycobacterial treatment regimen offered [azithromycin (10mg/kg/d) and moxifloxacin (10mg/kg/d)]. Following 3 months of treatment there was a reduction in the size of the lesion (Fig. 1B), with further improvement following cessation of treatment. M. llatzerense is a rapidly growing Mycobacterium. It has been recognized to colonize water systems, having been discovered in the water networks of European cities and3,4 Pennsylvania.5M. llatzerense has been implicated in other cases of human disease. Gomila et al6 isolated M. llatzerense in hemodialysis fluid in 2008. It was detected by polymerase chain reaction in a brain abscess,7 and a cutaneous lesion,8 both in immunocompetent adults and in a case of invasive pneumonia in a lung transplant recipient.9 Cárdenas et al10 reported positive culture for M. llatzerense from a subdiaphragmatic abscess occurring after multiple gastric surgeries. There are limited data available on the appropriate antibiotic therapy for M. llatzerense. The novel isolates first described by Gomila and colleagues were found to be susceptible to clarithromycin and ciprofloxacin. Cárdenas and colleagues reported susceptibility in their M. llatzerense isolate to moxifloxacin and clarithromycin. The combination of azithromycin and moxifloxacin was chosen for our patient based on a favorable side-effect profile. The combination was well tolerated by the patient and coincided with an improvement in the appearance of the skin lesion. While conservative management would be reasonable in an immunocompetent patient, our experience with the combination antimycobacterial therapy offers a treatment option to patients and their parents and may lead to earlier resolution of symptoms. ACKNOWLEDGMENTS We thank the patient and his parents for consenting to the publication of this case report.