Anerobic infection is precipitated by

Ans. d (All). (Ref. Harrison's Principles Medicine, 18th / Ch.31; Table 32-1)# Anaerobic organisms grow well when the oxygen free environment is available.# Impaired circulation due to trauma or some other reason leads to tissue necrosis if the impairment of circulation is severe and traumatized contaminated wound as such is also prone for the same, leading ultimately to anaerobic infection.Also remember:Acute necrotizing ulcerative gingivitis (ANUG) or Vincent's infection is caused by mixed anaerobes. Stress, poor oral hygiene, and tobacco and alcohol use are risk factors. This infection most commonly follows a debilitating illness or affects severely malnourished children. It has been known to complicate leukemia or to develop in individuals with a genetic deficiency of catalase. Peritonsillar abscess (quinsy) is a complication of acute tonsillitis caused mainly by a mixed flora containing anaerobes and group A Streptococcus. In submandibular space infection (Ludwig's angina), 80% of cases are caused by infection of the tissues surrounding the second and third molar teeth. This infection results in marked local swelling of tissues, with pain, trismus, and superior and posterior displacement of the tongue. Submandibular swelling of the neck can impair swallowing and cause respiratory obstruction. In some cases, tracheostomy may be life-saving. Cervicofacial actinomycosis is caused by a branching, gram-positive, non-spore-forming, strict/facultative anaerobe that is a part of the normal oral flora. This chronic disease is characterized by abscesses, draining sinus tracts, fistula, bone destruction, and fibrosis. It can easily be mistaken for malignancy or granulomatous disease. Actinomycosisless frequently involves the thorax, abdomen, pelvis, and CNS.