Byssinosis mechanisms

Although byssinosis has been recognized as a disease for more than a century, the underlying etiology and pathogenesis remain obscure. Four main mechanisms enzyme mediated (10,11,... 

A major argument against an endotoxin-like mechanism in byssinosis is the lack of fever (63). It is hypothesized, however, that exposure to endotoxin in cotton dust causes mill fever in new employees. With continued exposure, the worker becomes tolerant to this pyrexlal action of the endotoxin, but other effects of the LPS predominate, including complement activation and release of leucotaxic substances, both of which may ultimately lead to tissue damage. 

Another possible mechanism for byssinosis is the involvement of a specific hypersensitivity response. There are two major arguments for an allergic mechanism in byssinosis 1) there is... 

Another proposed mechanism of byssinosis is pharmacologic mediator release, especially histamine and 5-hydroxytryptamine (5-HT). Studies of histamine release following cotton dust exposure are complicated by the fact that cotton Itself contains histamine (98), the majority of which is found in the dust particle fraction below 20 P size (99). 

Our data showing normal serum complement levels in cotton mill workers (normal and byssinotic) does not support a complement activation mechanism for the pathogenesis of byssinosis, but the data does not eliminate the possiblity of complement activation in the etiology of byssinosis (Table V). As complement activation is a local reaction, small amounts of complement fragments sufficient... 

Potential etiologic agents in cotton dust that release histamine are shown in Table VII. Some of these are effector molecules having potent biological effects in minute concentrations, i.e. peptides, which may act directly to affect chemotaxis and leukocyte recruitment, and also to release histamine and stimulate respiratory smooth muscle contraction. These bifunctional effector molecules are of major importance in considering pathogenic mechanisms in byssinosis. 

Dust in the air of a mill engaged in the mechanical processing of cotton, flax, hemp, or certain other natural fibers is generally agreed to cause byssinosis (1 -4). No specific causative agent of byssinosis in the dust, however, has yet been unequivocally identified ( ). Certain bacteria dispersed from cotton fiber or bracts into mill air have been suggested to be a probable cause. 

Pickering, C. A.C., The search for the aetiological agent and pathogenic mechanisms of byssinosis a clinician s view of byssinosis. Proceedings of the 15th Cotton Dust Research Conference, Jacobs, R.R., Wakelyn, P.J., and Domelsmith, L.N., Eds., National Cotton Council, Memphis, TN, 1991, pp. 298-299. 

Byssinosis is a bronchopathy due to inhalation of cotton dust, generally considered as an occupational asthma, although the immunological mechanism is still discussed. Respiratory syndrome induced by inhalation of nylon dust (Flock worker s lung) is considered different from HP (Kern et al. 2000). Metal fume fever following inhalation of metal fumes (zinc, copper) is an influenza-like reaction with poor respiratory symptoms different from HP. 

---