Disease: causality

Rarely, a history of sensitization to an external agent can be identified. In these cases removal of the offending agent is the recommended treatment. Possible contributory or causal diseases, such as dry eye syndrome, acne rosacea, ocular allergic disease, or blepharitis, have been noted in up to 50% of episcleritis patients.These concurrent conditions should be treated if present. Full response to treatment in any patient who smokes can be delayed by a month or more. For this reason and because episcleritis... 

Experimental paradigm for identifying causal disease susceptibility genes. A/a and A y/A mice were fed micronutrient-balanced diets containing 70 or 100% calories for 90 days (for details see J. Kaput et al., Physiol Genomics, 2004. 18(3) p. 316-24),... 

Epidemiological studies of nickel-producing and nickel-using workers seldom indicate excess mortaUty from nonmalignant respiratory disease. Evidence for such effects exists mainly as a few reports of isolated incidents of asthma, pulmonary fibrosis, chronic bronchitis, and emphysema in nickel workers. Nickel may or may not play a causal role in these incidents (131). 

S Greenland. Probability logic and probability induction. Epidemiology 9 322-332, 1998. GM Petersen, G Parmigiam, D Thomas. Missense mutations in disease genes A Bayesian approach to evaluate causality. Am J Hum Genet. 62 1516-1524, 1998. 

Obviously, one looks for causes. That declines in one or another species have natural factor etiologies is unequivocal. The demise of American elms and of the chestnut were due to natural factors. Insect infestations, bacterial and fungal diseases, hurricanes, floods, freezes, droughts and many other stresses can cause extensive tree death (5). But in such declines typically only a single species is affected or climatic events caused decline in a delimited area. In almost all declines caused by natural events, the causal factors can be identified we know their precise etiologies. Natural events are always part of the natural environment and must be factored in when evaluating forest declines (Table I). 

Table 2 Most important faecal-orai water-borne infectious diseases with their causal agents...

A consistent pericardial edema in chickens gave rise to the term chick edema disease (chick edema factor) (I). Two known outbreaks of the disease in the broiler industry resulted in a great loss of chickens. A lipid residue from the manufacturing fatty acids, being used as a feed ingredient, was a principal source of the toxic substance. Contamination of the lipid component with polychlorodibenzo-p-dioxins was attributed as the causal agent. 

Schadt EE, Lamb J, Yang X, Zhu J, Edwards S, Guhathakurta D, et al. An integrative genomics approach to infer causal associations between gene expression and disease. Nat Genet 2005 37 710-7. 

Galassi G, Gentilini M et al (1998) Motor neuron disease and HIV-1 infection in a 30-year-old HIV-positive heroin abuser a causal relationship Clin Neuropathol 17(3) 131-135 Gherardi R, Lebargy F et al (1989) Necrotizing vasculitis and HIV replication in peripheral nerves. N Engl J Med 321(10) 685-686... 

Corynebacterium diphtheriae, which is non-sporing, is the causal organism of diphtheria, a disease which has largely been eradicated by immunization (Chapter 16). 

Bordetella pertussis is the causal organism of whooping-cough, a disease which... 

Haemophilus influenzae owes its specific name to the fact that it was thought to be the causal organism of influenza (now known to be a virus disease) as it was often isolated in cases ofinfluenza. It is the main cause ofinfantile meningitis and conjunctivitis and is one of the most important causes of chronic bronchitis. 

The causal organism of this disease, which must have existed undetected from time immemorial, was isolated and verified in 1977 and called L. pneumophila. 

Borrelia recurrentis causes a relapsing fever in humans. Borrelia vincenti is the cause of Vincent s angina in humans, an ulcerative condition of the mouth and gums. Borrelia burgdorferi is the causal organism of the tick-borne Lyme disease. 

Treponema pallidum is the causal organism of syphilis. Treponema pertenue causes the tropical disease called yaws. 

The risk of gout increases as the serum uric acid concentration increases, and approximately 30% of patients with levels greater than 10 mg/dL (greater than 595 pmol/L) develop symptoms of gout within 5 years. However, most patients with hyperuricemia are asymptomatic. Other risk factors for gout include obesity, ethanol use, and dyslipidemia. Gout is seen frequently in patients with type 2 diabetes mellitus and coronary artery disease, but a causal relationship has not been established. 

Any untoward medical occurrence in a patient or clinical investigation subject administered a pharmaceutical product and that does not necessarily have a causal relationship with this treatment. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal (investigational) product, whether or not related to the medicinal (investigational) product. 

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