Case of Mycobacterium mucogenicum in a home hemodialysis patient

Abstract

We present a case of a patient on home hemodialysis who developed Mycobacterium mucogenicum bacteremia. While infections with this particular organism are rare, disseminated infections have been reported and have been associated with significant morbidity and mortality. Diagnosis required appropriate cultures, understanding of natural habitat of organism and complete environmental analysis including blood, dialysis sample port, reverse osmosis and incoming water supply cultures. The patient was treated successfully with systemic antibiotics, removal of central venous catheter, patient education and complete exchange of the hemodialysis circuit.

Mycobacterium mucogenicumHand Infection in an Intravenous Drug Abuser

“…M. mucogenicum is the most common RGM implicated in central line-associated bloodstream infections [ 1 ]. Undertreatment of contaminated water sources has been implicated in infections including suboptimal chlorination of water and hemodialyzers treated with formaldehyde concentrations below those required to prevent growth of M. mucogenicum [ 4 , 9 ].…”

“…Due to slow growth of mycobacteria, diagnosis is often difficult and delayed. Appropriate blood cultures are critical and may need verification with repeat cultures [ 9 ]. Differentiation of mycobacteria to the species level is also complicated due to the slow growth rate of mycobacteria.…”

“…More importantly, as M. mucogenicum is an organism that resides in water bodies and soil, a complete environmental assessment needs to be performed. It is crucial to collect water samples from dialysis machine, RO, and incoming water supply [ 9 ].…”

“…RGM are difficult to eradicate from venous catheters since they survive by biofilm formation. Successful therapy requires removal of the catheter or other infected devices in addition to appropriate antimicrobial agents [ 1 , 4 , 9 ]. Management of M. mucogenicum infections includes both removal of indwelling catheters, similar to management of other RGM, and combination antimicrobial therapy [ 2 ].…”

“…El Helou et al found that use of combination antimicrobial regimens was superior to monotherapy and tended to be associated with lower relapse rate [ 6 ]. The current NTM practice guidelines do not explicitly state a specific treatment protocol for M. mucogenicum but do state that most isolates are susceptible to multiple antimicrobial agents including aminoglycosides, cefoxitin, clarithromycin, minocycline, doxycycline, quinolones, TMP-SMX, and imipenem [ 1 , 2 , 4 , 9 ]. Although the duration of treatment of nondisseminated RGM infection has not been established in the literature, prolonged therapy for several weeks to months appears to be necessary to eradicate infection [ 1 ].…”