showed that risk for MDR-TB is three times higher among recreational drug users than non-users. Shin et al.s study demonstrated that alcohol usage was linked to poorer outcomes in MDR-TB treatment; they also noted that a majority of subjects within their study (many of whom regularly used alcohol) were nevertheless cured by their aggressive treatment regimen.Non-compliance with treatment plans is often cited as a contributor to MDR-TB transmission and mortality. Indeed, of the 80 newly released TB-infected inmates in Fry et al.s study, 73.8% did not report visiting a community dispensary for further treatment. Ruddy et al. cite release from facilities as one of the main causes of interruption in prisoners TB treatment, in addition to non-compliance within the prison and upon reintegration into civilian life. Fry et al.s study also listed side effects of TB treatment medications (especially in HIV positive individuals), financial worries, housing insecurities, family problems, and fear of arrest as factors that prevented some prisoners from properly adhering to TB treatment. They also note that some researchers have argued that the short-term gains TB-positive prisoners receive, such as better food or work exclusion, may dis-incentivize becoming cured. In their World Health Organization article, Gelmanova et al. posit that non-adherence to TB treatment indirectly contributes to bacterial resistance. Although ineffective or inconsistent treatment does not "create" resistant strains, mutations within the high bacterial load in non-adherent prisoners can cause resistance. Nachega & Chaisson argue that inadequate TB control programs are the strongest driver of MDR-TB incidence.
Grade I & II are simpler fistulas and can be managed by Fistulotomy whereas Grade III-V are complex fistulas in which fistulotomy should be not be done. They should be managed by Fistula experts. Unlike Parks and St James University Hospital Classification, this correlation is quite accurate with Gargs classification. Therefore this new classification is useful to both surgeons and radiologists. Types
Depending on their relationship with the internal and external sphincter muscles, fistulae are classified into five types:

Extrasphincteric fistulae begin at the rectum or sigmoid colon and proceed downward, through the levator ani muscle and open into the skin surrounding the anus. Note that this type does not arise from the dentate line (where the anal glands are located). Causes of this type could be from a rectal, pelvic or supralevator origin, usually secondary to Crohns disease or an inflammatory process such as appendiceal or diverticular abscesses. Suprasphincteric fistulae begin between the internal and external sphincter muscles, extend above and cross the puborectalis muscle, proceed downward between the puborectalis and levator ani muscles, and open an inch or more away from the anus. Transphincteric fistulae begin between the internal and external sphincter muscles or behind the anus, cross the external sphincter muscle and open an inch or more away from the anus. These may take a U shape and form multiple external openings. This is sometimes termed a horseshoe fistula. Intersphincteric fistulae begin between the internal and external sphincter muscles, pass through the internal sphincter muscle, and open very close to the anus.