Infectious Disease Compendium

Mycobacterium

Microbiology

An acid fast bacillus. Always try to get susceptibility testing done, even if your lab complains (mine never do).

M. abscessus

Epidemiologic Risks

2015 review

M. abscessus is a group consisting of 3 species: M. abscessus (sensu stricto), M. massiliense, and M. bolletii.

M. massiliense more responsive to treatment (PubMed).

Non-Mtb are often soil or water organisms, causing disease often after penetrating trauma (acupuncture) or inhaling water (like showers). Outbreaks of leg folliculitis have been associated with pedicures (PubMed), the water is teeming with the organisms and evidently people shave their legs just before to maximally increase their chance of infection.

However, in (cystic fibrosis) patients there has been human to human world wide spread of a multi-drug resistant, virulent strain (Pubmed).

Can occur after 'lipotourism' where people go to Central America to get their cheap liposuction (PubMed). You get what you pay for.

Also cases with gastric banding (PubMed).

Anti-TNF-alpha therapy is associated with increased risk for both pulmonary and extrapulmonary non-Mtb mycobacteria, with MAI leading the list (PubMed).

One several reports of the bugs acquired from tattoo's (also M. haemophilum and M. chelonae) (PubMed). Hate to I&D the art to cure the infection.

One case was traced to the patients shower head.

Autoantibodies to gamma interferon is a risk (PubMed); patients act like HIV.

While M. bovis is usually obtained from unpasteurized milk, there can also be human to human airborne transmission (Pubmed).

Syndromes

Soft tissue infections.

Bacteremia in patients who use "cytokine-induced killer cell therapy for body beautification and health boosting (PubMed). People do the more peculiar things to get infections.

Pulmonary disease in cancer patients (PubMed).

Treatment

Soft Tissue: 4 to 9 months of clarithromycin (works poorly alone) plus surgical debridement. Often has an inducible macrolide resistance that do not show up in initial testing.

Pulmonary disease: Variable regimens reported. Amikacin + cefoxitin OR imipenem (not meropenem or ertapenem) plus a macrolide at maximal dose. Maybe linezolid or tigecycline. Maybe it should be resected as well (PubMed).

Clarithromycin, ciprofloxacin, and doxycycline, together with an initial regimen of amikacin and cefoxitin for the first 4 weeks of hospitalization resulted in an 84% clinical response (PubMed).

M. abscessus has inducible clarithromycin resistance, M. massiliense does not (PubMed).

Notes

M. avium-intracellulari

Epidemiologic Risks

Found in water of all kinds the world over. Having GERD is a risk factor for normal hosts to develop pneumonia (PubMed).

Syndromes

Disseminated and focal disease of all types in HIV (usually with CD4 < 50) and hairy cell leukemia. Occasionally will cause indolent progressive pneumonia in 'normal' (how normal can they be if they get MAI) hosts and occasional soft tissue infections after penetrating injuries.

Autoantibodies to gamma interferon is a risk (Pubmed); patients act like HIV.

Treatment

Multiple drugs.

In AIDS: clarithromycin OR azithromycin PLUS rifampin OR rifabutin, PLUS ethambutol PLUS/MINUS quinolone AND/OR amikacin. Response is usually disappointing.

Prevention is preferred in HIV with CD4 < 50 with either clarithromycin 500 mg bid or azithromycin 1250 mg weekly.

In non AIDS pneumonia: clarithromycin OR azithromycin AND rifampin OR rifabutin AND ethambutol for at least a year. Amikacin can also be used (I used it inhaled in one patient and got very good control of symptoms. Remember, anecdotes are nearly worthless). When MAC patients relapse, it is often a new infection with a different genotype. In the nodular/bronchiectatic patients, 3x a week rx is just as good (presented at 2011 IDSA). Expect a 75% response rate, which I do not believe. There is a study that suggest response rates are a 39%, which is in line with what I see clinically (PubMed).

Curiously, only susceptibility to macrolides correlates with success; the sensitivity of the other agents doesn't seem to matter.

Notes

MAI can be contaminant/part of the upper airway, so proving pneumonia requires both excluding other diseases and isolating MAI on multiple specimens over time. Although susceptibility testing is problematic, I always get it.

In non-AIDS lung disease, intracellulari is worse than them what avium: less response, more progression (PubMed).

M. bovis/BCG (Bacille Calmette-Guérin)

Epidemiologic Risks

It is MTB complex and it is complex indeed, including M. tuberculosis, M. africanum, M. canettii, M. bovis, M. caprae, M. pinnipedii, M. microti, and M. mungi.

M. bovis: contaminated milk.

Paleomicrobiology suggests that MTB came first and we gave it to cows about 40,000 years ago, who bred a new lineage. In contrast, Tb and leprosy diverged 36 million years ago, before there were humans. Cool Beans.

In Mexico, cow workers (different than coworkers, which I always see as cow orker) commonly have latent disease The overall prevalence of latent tuberculosis infection (LTBI) was 76.2% by TST and 58.5% by lymphocyte assays (PubMed).

In Africa, M. bovis from cows is a significant source of MTB in humans (PubMed).

In England it is in the badgers and in Africa the black rhino (PubMed). Good thing traditional Chinese pseudo-medicine is helping to drive them into extinction (SBM).

BCG: given to both prevent MTb (it prevents both infection and progression (PubMed))and used therapeutically in bladder cancer. It is a M. bovis that has been multiply passaged in the lab to (mostly) decrease virulence.

Syndromes

M. bovis acts like MTb. In one series it accounted for almost 50% of pulmonary "Tb" (PubMed) in hispanics; all were resistant to PZA.

BCG: can cause disseminated disease in HIV and other immunoincompetent patients. It can cause both local (epididymitis / prostatitis) and disseminated disease in patients receiving it for bladder cancer.

Treatment

Isoniazid AND rifampin.

In bladder cancer patients is can be resistant to INH. Recommendations for rx of cancer treatment related illness(PubMed):

If T > 38.5 for >24: Isoniazid for 3 months.

If Localised M. bovis BCG infection (eg, epididymitis / prostatitis)), rifampin and Isoniazid with or without fluoroquinolones for 3–6 months

Systemic M. bovis BCG infection and/or sepsis: rifampin, Isoniazid, and ethambutol with or without fluoroquinolone or cycloserine; with or without corticosteroids; duration not specified.

Notes

Mycobacterium celatum

Epidemiologic Risks

Ferrets (PubMed).

Syndromes

Disseminated disease in immunocompromised patients (mostly AIDS), and the occasionally unlucky immunocompetent persons.

Treatment

Few cases to say for sure, resection if possible and clarithromycin, ethambutol, and ciprofloxacin and been tried (PubMed).

Notes

M. chelonae

Epidemiologic Risks

Penetrating environmental trauma. #1 atypical after LASIK. Outbreaks of leg folliculitis have been associated with pedicures (PubMed), the water is teeming with the organisms and evidently people shave their legs just before to maximally increase their chance of infection.

Also can occur after liposuction and a form of SCAM called mesotherapy (PubMed). Also following bee venom 'therapy' (PubMed), although why anyone would think a practitioner of mesotherapy or bee venom therapy would have any understanding of aseptic technique is beyond me.

One several reports of the bugs acquired from tattoo's (also M. haemophilum and M. chelonae) (PubMed). Hate to I&D the art to cure the infection. I need a tat for my mid-life crisis. Any suggestions?

Syndromes

Most are soft tissue infections, occasional other infections (prosthetic valves).

Treatment

Several months (end point is cure) of clarithromycin is usually preferred, it is often susceptible against amikacin OR imipenem OR tobramycin.

Notes

Debride (it's pronounced dee breed; dee bride is de woman who walks down de aisle of de church).

Mycobacterium chimaera

Part of the MAC group (PubmMed) Outbreak in a open heart program. From water circuits of heater-cooler units connected to the cardiopulmonary bypass to the air and then to the patient (PubMed) Mostly PVIE and occasional sternal wound infection (PubMed) .

M. conceptionense

Epidemiologic Risks

Soil organism

Syndromes

Two soft tissue infections and a breast implant infection.

Treatment

Unknown.

M. doricum

Epidemiologic Risks

Soil organism

Syndromes

One bone/soft tissue infection and one AIDs related meningitis.

Treatment

Unknown, but what few specimens tested are pan-susceptable to the usual drugs to treat atypical and typical mycobacteria.

Notes

M. florentinum

Epidemiologic Risks

?

Syndromes

Lymphadenitis and pneumonia. Slow growing.

Treatment

"The isolate was susceptible to amikacin and clarithromycin with MICs of 0.5 &mcg/mL but was resistant to ciprofloxacin (MIC 8 &mcg/mL), according to Clinical and Laboratory Standards Institute guidelines. Other drugs tested (with corresponding MICs) included ethambutol (4 &mcg/ mL), gatifloxacin (2 &mcg/mL), moxifloxacin (1 &mcg/mL), rifampin (0.12 &mcg/ mL), and streptomycin (0.5 &mcg/mL) (PubMed)."

Notes

M. fortuitum

Epidemiologic Risks

Penetrating environmental trauma. Outbreaks of leg folliculitis have been associated with pedicures, the water is teeming with the organisms and evidently people shave their legs just before to maximally increase their chance of infection.

Also can occur after a form of SCAM called mesotherapy (PubMed) and as a complication of insulin infusion sites (PubMed) and injections from tradiational Vietnamese pseudo-medicines (PubMed).

Also cases with gastric banding (PubMed).

Pulmonary disease, soft tissue and blood stream infections in cancer patients (PubMed).

Syndromes

Most are soft tissue infections, but can occur where ever the trauma occurred: joints etc.

Treatment

Several months (end point is cure) of 2 drugs for severe with amikacin OR cefoxitin OR ciprofloxacin OR clarithromycin OR doxycycline OR tmp/sulfa OR imipenem , usually for six months.

Notes

Debride. See note for M. chelonae. Has an inducible erm gene that may fool you: it can look clarithromycin susceptible and not be.

M. genavense

Epidemiologic Risks

Environmental, it occurs in a wide variety of domestic animals esp birds.

Syndromes

Disseminated disease in HIV; pneumonia in the immunoincompetent.

Treatment

Oral clarithromycin plus rifabutin have been used in humans. Rifabutin, amikacin, and ethambutol are effective in animal models (PubMed).

Notes

M. gordonae

Epidemiologic Risks

Water.

Syndromes

Pneumonia.

Treatment

Clarithromycin so few cases it is hard to say. Case reports of doxycycline and quinolones being used.

Notes

Can cause pseudo outbreaks from contaminated water.

M. haemophilium

Epidemiologic Risks

Environmental. Usually seen in the immunoincompetent esp lymphoma. There was an "outbreak after permanent make-up of the eyebrows performed by the same freelance artist" (PubMed). There were a pair of cases in Seattle from tattooing, but it is Seattle. What would you expect from Seattle?

Syndromes

Skin ulcerating lesions, soft tissue, bone, joint and disseminated disease and pneumonia.

Treatment

Some combination of amikacin, ciprofloxacin, clarithromycin, rifampin and rifabutin (active in vitro) until cure.

Notes

Requires special media.

M. jacuzii

Epidemiologic Risks

Hot tubs.

Syndromes

A plastic surgeon got it from his hot tub and infected a bunch of breast implants. Really (PubMed). BTW: he infected then in the OR, not the hot tub.

Treatment

Removal of the implant was curative, some were treated with ciprofloxacin and doxycycline for 6 to 12 weeks. Isolates were susceptible to ciprofloxacin, ofloxacin, doxycycline, amikacin, and ethambutol.

Notes

Resistant to clarithromycin, sulfamethoxazole-trimethoprim, rifampicin, isoniazid, capreomycin, cycloserine, tobramycin, streptomycin, cefoxitin, and imipenem.

M. kansasii

Epidemiologic Risks

Water supplies.

Syndromes

Chronic pneumonia, disseminated disease in the immunoincompetent, the occasional focal infection.

Treatment

Isoniazid PLUS rifampin PLUS ethambutol.

Notes

Clarithromycin can be used in place of rifampin in HIV patients; duration of rx for pulmonary disease is at least 18 months.

M. lentiflavum

Epidemiologic Risks

found in water (PubMed).

Syndromes

pneumonia and lymphadenitis

Treatment

not enough cases to say for sure; clarithromycin plus some standard Tb drugs.

M. leprae and M. lepromatosis

Epidemiologic Risks

Endemic in most of the world, it is spread person to person. It is in the armadillo’s in the SW, who got it from humans and have been kind enough to give it back (PubMed).  The range of leparous armadillos is spreading (Pubmed)cdc.gov/eid/article/21/12/15-0501_article">PubMed). And it is in the red squirrels of England(Pubmed). Both animals got the disease of humans.

It is the oldest human disease; read this amazing article (PubMed).

Syndromes

Lepromatous leprosy: symmetric skin nodules, plaques, and a thickened dermis on cool areas of the body; the upper respiratory system, esp the nasal mucosa. Peripheral neuropathy is generalized and symmetric and involves hands and feet.

Tuberculoid leprosy: few anesthetic hypo pigmented dry, scaly, plaques with distinct elevated and erythematous borders of variable size. Neuropathy occurs in the same distribution as the skin lesions.

Borderline leprosy: features of both tuberculoid leprosy and lepromatous leprosy.

Treatment

Multibacillary leprosy (positive skin smears): Rifampicin 600 mg once a month PLUS dapsone 100 mg daily PLUS clofazimine 300 mg once a month and 50 mg daily for 12 months. Paucibacillary leprosy (Negative skin smears). Rifampicin: 600 mg once a month PLUS dapsone 100 mg daily for six months.

Notes

I advise visiting the WHO site at http://www.who.int/lep/ for all your leprosy information. In the West it is a rare disease where few have expertise.

M. malomense

Epidemiologic Risks

Syndromes

Occasionally disseminated disease, cavitary pneumonia, and lymphadenitis.

Treatment

Notes

M. marinum

Epidemiologic Risks

Brackish salt water exposure. Also swimming in South Pacific World War Two bomb craters filled with water (PubMed).  And handling fish.

Syndromes

Infection (red/purple bumps that subsequently ulcerate) on cool parts of the body where there was trauma and subsequent inoculation.

Treatment

Clarithromycin and ethambutol for a prolonged period of time (3 - 6 months as a rule).

Notes

Depending on the site, debridement may be in order.

M. microti

Epidemiologic Risks

It is found in voles, rodents. camels and llamas.

Syndromes

Pneumonia in normal people, it grows slowly.

Treatment

Isoniazid, rifampin, and pyrazinamide and Isoniazid, ethambutol, rifampin, streptomycin, and pyrazinamide have been used with success (PubMed).

Notes

M. mucogenicum

Epidemiologic Risks

Tap water, found in transplant patients can cause a hepatitis.

Syndromes

Catheter infections in transplant patients and can cause a hepatitis. Infection in cancer patients (PubMed).

Treatment

Notes

Depending on the site, debridement may be in order, remove the line.

M. neoaurum

Epidemiologic Risks

Tap water, found in transplant patients.

Syndromes

Catheter infections in transplant patients. Infection in cancer patients (PubMed).

Treatment

"Successful treatment of M. neoaurum bloodstream infection has most commonly included several weeks of combination antimicrobial therapy, including macrolides, fluoroquinolones, or aminoglycosides, and removal of devices" (PubMed).

Notes

Remove the line.

Mycobacterium porcinum

Epidemiologic Risks

Water, from municipal water sources (PubMed).

Syndromes

"Clinical infections included wound infections (62%), central catheter infections and/or bacteremia (16%), and possible pneumonitis (18%) (PubMed)."

Treatment

Ciprofloxacin, sulfamethoxazole, and linezolid and susceptible or intermediate to cefoxitin, clarithromycin, imipenem, and amikacin (PubMed).

Notes

M. simiae

Epidemiologic Risks

Syndromes

Treatment

Notes

M. szulgai

Epidemiologic Risks

"M. szulgai has been recovered from environmental sources, including a snail, aquarium water, swimming pool water, and tropical fish" (PubMed).

Syndromes

Pneumonia (mimics Tb) and extrapulmonary disease in the immunosuppressed.

Treatment

"On average, treatment lasted for 12 months (range, 6–26 months) and consisted of rifampin or rifabutin with ethambutol and clarithromycin and/or quinolones (PubMed)."

Notes

M. tuberculosis complex (2013 Review)

Epidemiologic Risks

It is MTB complex and it is complex indeed, including M. tuberculosis, M. africanum, M. canettii, M. bovis, M. caprae, M. pinnipedii, M. microti, and M. mungi.

Person to person, it is spread by coughing (PubMed). Smoking increases your risk of acquiring Tb (PubMed). So cover your mouth when coughing. Duh. Coughless patients can still spread the disease, but are less infectious.

As the cough fades, and it takes about 2 weeks, so does the risk of spread as judged by culture conversion.(PubMed).

Risk factors for developing active disease include upper lobe scarring in CXR, steroid use, immunodeficiency (esp AIDS), silicotic lung disease, gastric bypass, gastrectomy (PubMed) and celiac disease.

And diabetes increases risk. And NSAID use(PubMed). But statins decrease the risk (PubMed). Go figure.

Hematologic, head and neck, and lung cancers have a 9-times higher rate of developing active tuberculosis (PubMed).

In clusters, not hospitals, 13% of Tb was transmitted by smear negative, but culture positive patients (PubMed).

Smoking increases the chances of getting TB and of relapsing after therapy (PubMed).

There is nothing like HIV and organ transplants and anti-TNF antibody (PubMed) therapy to allow Tb to cut loose, reactivate and kill, often with miliary disease.

In West Africa, 50% of cases of Tb are due to M. africanum (Review).

Elephants. there is a case of acquisition from an elephant (PubMed). Up to half of Asian elephants may have latent TB (PubMed). 5% of Asian elephants in the US have TB. And some bonobos gave it to their keeper (PubMed). Plus humans can spread MTb to cows (PubMed). And it kills 30% of the wild boars in Spain.

Evidence has been found for the organism in 17,000 year old extinct bisons (Plos). Ancient tubercular bovines. How cool is that?

Syndromes

-PPD positive, aka latent Tb (NEJM Review):

This means prior exposure to the disease and the patient still have living AFB in them. And the AFB are everywhere. The took a bunch of people who had latent TB and used PCR on various tissues and found MTB in "Lung specimens from most subjects (36) were positive... as were specimens from the spleen (from 35 subjects), kidney (from 34), and liver (from 33) (PubMed)."

Extra-pulmonary and disseminated disease are less likely to have a positive ppd (PubMed). But really, positive or negative, a ppd does not help determine if the patient has active disease. It's only real utility is screening in exposure to look for latent disease.

5 mm is positive for HIV. This, while the official cut off, may be incorrect as it appears that AIDS with Tb are more like to be anergic than to have a smaller PPD. The size of the ppd doesn't fade, it switches off. 10 mm is positive for exposures and people at risk (health care workers fore example). 15 mm is positive for no risk/expose patients (a 35 yo from Des Moines who has spent their life cloistered).

I am glad I converted and did my INH (my year without beer) for if re-exposed I have 79% lower risk of progressive tuberculosis after reinfection than uninfected individuals (PubMed). Not that I am suggesting, like those anti-vaccine wackaloons who expose their children at chickenpox parties, that you run out and suck in a lung full of tubercular air.

The BCG is to be ignored in the evaluation of a PPD; half of BCG never get a positive PPD, 90% of the remaining revert to ppd negative in 5 years.

You can get an interferon assay (Quantiferon or T SPOT), they are more specific, but not more sensitive than a PPD (each will miss around 20ish% of cases depending on populations studied; they never rule out disease, they are of more benefit in sorting out whether a PPD is positive from MTB or an NMTB). It may not be reliable in pregnancy (PubMed).

However, in low risk populations a positive is more likely to be a false positive and if you do a TST and a QuantiFERON the results will not agree (PubMed).

-Pulmonary:

Thick walled cavitary upper lobe pneumonia is the most common manifestation, can appear as focal infiltrates.

Here is a scary little fact if you do infection control: 37% of US pulmonary Tb cases were sputum smear negative. Risks: foreign born, in jail or HIV infected. The good news? Smear negative TB cases had lower mortality, independent of HIV status (PubMed).

-Extrapulmonary:

Pleural TB is the most common extrapulmonary manifestation; the adenosine deaminase is useful in making the diagnosis (PubMed).

There was an outbreak of 30 cases of primary innoculation TB from acupuncture (PubMed). What do you expect when acupuncture practitioners have almost no understanding of infection control. There is one photo on the internet of acupuncture with gloves and watching the videos with the eye of infection control will give you the heebie jeebies.

Tb can affect any organ; miliary (or disseminated) and meningitis are the worst. Tb adenitis is common and it drives me nuts how often the nodes are excised and only sent for pathology.

Can cause erythema nodosum and nodular vasculitis (PubMed).

And, like so many other infections, TB increases the risk for venous thromboembolism (PubMed).

Treatment

- there is molecular testing available to looks for resistance before susceptability is back; ask your state lab.

- MDRTb and XDRTb are increasing in incidence. In XDRTB, later-generation fluoroquinolones (moxifloxacin) for the treatment of XDR TB significantly improves treatment outcomes, even though drug-susceptibility testing demonstrates resistance to the fluoroquinolone (PubMed).

The old Soviet prisons were breeding grounds for MDTB(PubMed).

- Linezolid and delamanid (PubMed) are useful in treating MDRTB.

- for TB meningitis there may be an advantage to using linezolid up front with a faster response (PubMed).

- Latent Tb/PPD positive (2015 Review): all new converters, regardless of age, should be encourage to take 6 or 9 months of isoniazid (and B6). I know the powers that be suggest 6 months, but if you prescribe 9 months just maybe they will take it for 6, and 9 months is better than 6. Those older than 65 have an increased risk of adverse reactions (PubMed).

- once-weekly rifapentine 900 mg plus isoniazid 900 mg for three months is superior (half the cases of subsequent Tb) to the standard 9 months of isoniazid; better adherence and fewer adverse events (PubMed).  Maybe.  In one comparison on INH,  those of white race, female sex, older age, and lower BMI were more likely to have flu like symptoms (PubMed).

- Rifampin and isoniazid for three months takes the risk from 7% to 4% and is what is used in the UK.

- when to check LFT's? The guidelines say "Routine monitoring is not necessary. However, for patients who have preexisting liver disease or who develop abnormal liver function that does not require discontinuation of the drug, liver function tests should be measured monthly and when symptoms occur", but perhaps everyone, esp HIV, should have LFT's checked at 2 weeks (PubMed).

- All old converters at risk for reactivating Tb (steroid use, hematologic malignancy, apical scarring on CXR, HIV, gastric bypass, silicotic lung disease) or from an endemic area should also be strongly encouraged to take 9 months to a year of isoniazid (and B6). Pregnancy is not a reason to delay therapy by current recommendations but pregnancy always makes one skittish (although perhaps increased hepatotoxicity).

- INH resistant exposure, 4 months of rifampin alone or PLUS ethambutol OR a quinolone. Do NOT use rifampin and PZA, too much liver toxicity, a debatable issue (PubMed). And rifampin may decrease quinolone susceptibility (PubMed).

- Active Disease: At least four drugs at maximum dose should be started while awaiting sensitivity testing and if patient has been on antitubercular drugs before, they should include 2 drugs they have not seen before. Isoniazid, rifampin, pyrazinamide, ethambutol, streptomycin are the five first line agents with quinolones (esp moxifloxacin) in reserve. Linezolid is effective as well (PubMed). DO NOT USE Ciprofloxacin for the treatment of MTb, use moxifloxacin or levofloxacin.

- Duration is 6 months to 18 months depending on the location of the infection. AIDS patients with 'standard' therapy ie 6 months or three times a week therapies have a higher relapse rate (PubMed).

Longer treatment is better than shorter and daily is better than intermittent dosing (PubMed).

There is a suggestion that longer treatments of extra-pulmonary disease may increase mortality (PubMed): "The relationship between mortality and therapy duration for each type of EPTB was a unique “V” shaped curve, with the lowest mortality observed at different therapy durations for each, beyond which mortality increased."

And an interesting meta analysis suggests that all, that's all, forms of TB could benefit from steroids (PubMed); however the data is thin for pulmonary disease.

Low serum levels are associated with clinical failure and drug resistance (PubMed) and increased levels with liver toxicity (PubMed) so perhaps blood levels should be done more often

Notes

- In evaluating a PPD the BCG history is to be IGNORED. Its all caps for a reason. The chance that the PPD is positive from a BCG >10 years after receiving a BCG is at most 0.1% to 2.3% (PubMed).

- All BCG vaccines may not be equal in eliciting an immune response. BCG Japan strain elicits a more robust immune response than the BCG Danish, BCG Glaxo, or BCG Pasteur (PubMed), (PubMed); although they may be equivalent in preventing infection (PubMed).

- Booster Effect: someone has been exposed to Tb in the distant past, and they have immunological memory. They do not react to the first PPD, but it is enough of an immunologic challenge that they respond to the next PPD. This is why you do two step testing (baseline and one week later) in people with potential distant exposure history, it allows you to differentiate from old PPD positive from a new converter.

- Smear positive patients need to be in isolation until smear negative. Most patients will be smear and culture negative at two weeks. Don't argue with your infection control practitioner. Believe me, when it come to Tb isolation, they know more than you do.

- Directly Observed Therapy is best for all infectious Tb.

- Prednisone 60 - 80 mg po qd for moderate to severe meningitis, tapered over 6 - 8 weeks, is of benefit.

- for tuberculoma if steroids are not working to control symptoms, consider thalidomide (PubMed).

- Also, 150 mg of aspirin decreases mortality as well; the wonder drug that works wonders (PubMed).

- Diagnosis of Tb is difficult, with the exception of cavitary pulmonary disease, AFB stains, culture and PCR have poor yield, so in the right clinical situation, empiric therapy and watching for response is a reasonable approach. When in doubt, why, that's the reason for Infectious Disease doctors.

- Vitamin D may be important in immunity against MTb (PubMed), (PubMed) and adding vitamin D may increase resolution time (PubMed) (PubMed) (PubMed).

Smoking and diabetes increase mortality (PubMed), so if you get TB, do not smoke a diabetic. I think that is what they meant.

- of interest, the Giant African pouched rats can be trained to smell tuberculosis (PubMed) in sputum samples to increase detection by 44% over standard diagnostic microscopy. This is the same rat that brought monkeypox to the US a few years back, and a source of bushmeat in Africa. Mmmmm. Giant African pouched rat. So much better than Guinea pig.

M. ulcerans

Epidemiologic Risks

Probably spread by mosquitos (PubMed).

Syndromes

I don't know. M. ulcerans. Think it might cause an ulcer? Its name is Buruli ulcer. In places like Austrailia, Mycobacterium ulcerans can present like an edematous cellulitis (PubMed).

Treatment

4 weeks of streptomycin and rifampicin followed by 4 weeks of rifampicin and clarithromycin has similar efficacy to 8 weeks of streptomycin and rifampicin; however, the number of injections of streptomycin can be reduced by switching to oral clarithromycin after 4 weeks (PubMed).

It will not grow above 37 degres so heat will cure it (PubMed).

Notes

M. wolinskyi

Epidemiologic Risks

Cosmetic surgery (PubMed)

Syndromes

Treatment

clarithromycin, amikacin, and ciprofloxacin have been used.

Notes

M. xenopi

Epidemiologic Risks

Syndromes

Musculoskeletal, pulmonary disease, joint infections (PubMed).

Treatment

At least 3 of rifampin, ethambutol, isoniazid, ciprofloxacin, and clarithromycin for maybe 6 months.

Notes

M. yongonense

Epidemiologic Risks

Syndromes

Pulmonary disease (PubMed).

Treatment

Perhaps: rifabutin, ethambutol, and clarithromycin (PubMed).

Notes