ali somily md. all mycobacterial species except those that cause tuberculosis (tb) mycobacterium...

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Ali Somily MD

All mycobacterial species except those that cause tuberculosis (TB)

Mycobacterium tuberculosis complex includes M. tuberculosis including M. tuberculosis subsp canettiM.bovisM. bovis BCG strainM. africanumM. capraeM. microti M. pinnipedii

Leprosy (M. leprae).

1954 Runyon first NTM classification >100 NTM species Other names

Mycobacteria other than tuberculosis (MOTT)

AtypicalEnvironmentalOpportunistic

Variable pathogenicity and geographic regions

40% cause diseases in human Immunosuppressed host

Water, soil, food and animals Does not spread from person to another Relatively resistant to chlorination and

ozonization Outbreak and Pseudo-outbreak in the

hospital HIV and dialysis patients Improve laboratory methods

reporting MAC 40%,rapidly growing 10%,15%

unknown,25% M.gordonae,2.5% M.kansasii(MW USA and UK) and 1% M.xenopi (Ontario)

Rapid Growers Days in broth and

< 1 week in solid media

M.abscessus M.chelonae M.fortutum

Slow Growers 1-2 weeks in broth

and 2-4 weeks in solid media

M.avium M.kansasii M.scrofulaceum M.ulcerans M.xenopi M.gordonae

M.leprae cannot be cultured M.marinum lower temperature required M.haemophilum lower temperature

required and iron need to be added M.ulcerans lower temperature required M.genavense very slow growth in broth DNA probes for MAC, M. kansasii and M.

gordonae available Identification and sensitivity

Risk factors Immunosuppression ( HIV, Medications )AgingBCG vaccinationCystic fibrosisFibronodular bronchiectasis

Common clinical syndromes:1. Lymphadenopathy2. Chronic pulmonary disease3. Skin and soft tissue infections (often

associated with trauma or a foreign body) sometimes with extension to bone and joint

4. Disseminated disease.

Pulmonary disease Definition Usually adults Symptoms of cough, sputum production,

weight loss Two or more sputum isolates or one

isolate from,BAL,Bx, sterile site Distribution of isolates varies regionally

Pulmonary disease Common etiological agents M. avium complex(MAC) M. kansasii M. abscessus M. xenopi

Elderly men with COPD Middle aged to elderly Non- smoking

women CF patients Hypersensitivity pneumonitis

M.Kansasii Similar to TB US midwest and

south AFB positive Probe positive HIV CD4 <200

pulmonary and disseminated

M..xenopi UK, Northern

Europe and Canada, less common in US

Rural /farm area Very good

outcome

Pulmonary disease Treatment Treatment with combined antimicrobials Resection if localized

Lymph node disease Definition Usually < 5 years of age Unilateral, submandibular site most

common Onset of symptoms subacute Skin induration and sinus tract

formation may occur R/O TB MAC (80%) is the most common

followed by M. scrofulaceum Dx Fine needle or excisional Bx

Lymph node disease

Common etiological agents

MAC M. kansasii M. malmoense M. haemophilum

Uncommon etiological agents

M. scrofulaceum M.fortuitum/

peregrinum M.abscessus/

chelonae

Lymph node disease Treatment Surgical resection is usually curative

Skin/soft tissue/bone/joint and tendons

Definition History of trauma or superficial

laceration Presence of a foreign body

Skin/soft tissue/bone/joint and tendons

Common etiological agents

M. marinum M.

fortuitum/peregrinum

M. abscessus/chelonae

M. ulcerans

Uncommon etiological agents

MAC M. kansasii M. terrae M. haemophilum

Water ,fish Lake, bay,ocean,pool,aquarium 1-2 month IP granulomatous nodular

– ulcerative lesions (hands) Bx for diagnosis

Fish tank granuloma/ M.marinum

Buruli ulcer /M.ulcerans

Chronic cutanous ulcer

Africa mostly Debridment

Skin/soft tissue/bone/joint and tendons

Treatment Debridement plus combined drug

therapy

Disseminated Definition HIV or other immunosuppressive

disease Symptoms: fever, weight loss, diarrhea Any site possible No trauma necessary

Disseminated Prevention & treatment Prevention of MAC in HIV by prophylaxis Treat positive blood culture aggressively

Disseminated Common etiological agents

MACM. genavenseM. abscessus/chelonaeM. haemophilum

Any mycobacterium may cause disease in association with significant immunosuppression HIV CD4 < 50), and any localized lesion may disseminate.

M.fortutum M.abscessus M.chelonae Skin and soft tissue infection after truma

, post-op,cardiac ,mammoplasty and cosmotic

Pulmonary M.abscessus>M.fortutum Indolent, progressiveCavitary uncommonMild systemic symptoms

Worldwide –esp in tropical countries Transmission rout unknown Can not be cultured Syndromes

Lepromatous TuberculoidMixed

Treatment 6-months to 2 years Dapsone + Rif +/- clofazimine

Principles of Treatment of NTM Disease

1. Patients should be carefully evaluated to determine the significance of an NTM isolate. The presence of the organism in a sterile site or repeatedly from airway secretions in association with a compatible clinical and radiologic picture confirms the diagnosis.

2. Treatment of rapidly growing mycobacteria should be guided by in vitro susceptibilities. Other drug susceptibility testing is not standardized.

3. Treatment should usually combine at least two drugs of proven efficacy.

4. Contact follow-up is not necessary since NTM are not transmitted from person to person.

5. Duration of therapy has not been determined; in general, 6-12 months is required following negative cultures.

6. In soft tissue infections, because of rapidly growing mycobacteria, a combination of debridement and treatment with antimicrobials is recommended. For selection of antimicrobial agents, consultation with the laboratory should be undertaken regarding the reliability of in vitro testing.

MAC Clarithromycin or azithromycin + ethambutol+Rifampin

M. xenopi Rifampin+Ethambiotol +INH

M. kansasii Rifampin + Ethambutol M. malmoense Rifampin or Ethambutol M. marinum Rifampin or Clari +

Ethambutol 2-3 months Rapid growers doxycycline, amikacin,

imipenem, quinolones, sulfonamides, cefoxitin, clarithromycin

M. haemophilum Clarithromycin, Rifampin Cipro or Amikacin

M. genavense Clarithromycin, Rifabutin or AmikacinEthambutol

M. ulcerans Clarithromycin, Rifampin, Ethambutol or PAS ( Paraaminosalicylic acid)

MAC prophylaxis Azithromycin , Clarithromycin or Rifabutin 300 if CD4 <50x 106/L

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