Photosensitive dermatitis

Niacin Nicotinic acid, nicotinamide Coenzyme in oxidation and reduction reactions, functional part of NAD and NADP Pellagra—photosensitive dermatitis, depressive psychosis... 

Pellagra is characterized by a photosensitive dermatitis. As the condition progresses, there is dementia, possibly... 

Suggested Alternatives for Differential Diagnosis Bovine viral diarrhea/mucosal disease, rinderpest, bluetongue, foot and mouth disease, vesicular stomatitis, pneumonic pas-teurellosis, photosensitive dermatitis, infectious bovine rhinotracheitis, theileriosis, rabies, and the tick-borne encephalitides. 

Murata, Y. etal., Photosensitive dermatitis caused by pyridoxine hydrochloride,. /. Am. Acad. Dermatol., 39, 314, 1998. 

Correct choice = B. At high concentrations, tetracycline enters mammalian cells by diffusion and interacts with mitochondrial ribosomes, blocking access of the amino acyl-tRNA to the mRNA-ribosome complex at the acceptor site. Severe photosensitive dermatitis occurs when the patient receiving tetracycline is exposed to sun or ultraviolet rays. 

Thami GP, Kaur S, Kanwar AJ. Delayed reactivation of haloperidol induced photosensitive dermatitis by methotrexate. Postgrad Med J 2002 78(916) 116-7. 

Pellagra is characterized by a photosensitive dermatitis, like severe sunburn, typically with a butterfly-like pattern of distribution over the face, affecting aU parts of the skin that are exposed to sunlight. Similar skin lesions may also occur in areas not exposed to sunlight, but subject to pressure, such as the knees, elbows, wrists, and ankles. Advanced pellagra is also accompanied by a dementia or depressive psychosis, and there may be diarrhea. Untreated pellagra is fatal. 

Despite our understanding of the biochemistry of niacin, we still cannot account for the characteristic photosensitive dermatitis in terms of the known metabolic lesions. There is no apparent relationship between reduced availability of tryptophan and niacin, and sensitivity of the skin to ultraviolet (UV) light. The only biochemical abnormalities that have been reported in the skin of pellagrins involve increased catabolism of the amino acid histidine leading to a reduction in the concentration of urocanic acid, a histidine metabolite that is the major UV-absorbing compound in normal dermis (see Figure 10.6). 

Uses. Sun screens are no substitute for light-impermeable clothing and sun avoidance. They are, however, beneficial in protecting those who are photosensitive due to drugs (below) or to disease, i.e. for photodermatoses such as photosensitivity dermatitis, polymorphic light eruption, cutaneous porphyrias and lupus erythematosus. Methodical use of sunscreens appears to reduce the incidence of squamous cell carcinoma in vulnerable individuals. 

Murata Y, Kumano K, Ueda T, Araki N, Nakamura T, Tani M. Photosensitive dermatitis caused by pyridoxine hydrochloride. J Am Acad Dermatol 1998 39(2 Pt 2) 314-17. 

Selenium sulfide can cause local irritation (SED-12, 685). Photosensitive dermatitis (pityriasis versicolor) occurred in an adult man after a second application of 2.5% selenium sulfide (12). 

Cook N, Freeman S. Photosensitive dermatitis due to suu-screeu allergy iu a child. Australas J Dermatol 2002 43(2) 133-5. 

Few adverse reactions to cyclamate have been reported, although its use has been associated with instances of photosensitive dermatitis. ... 

Yong JM, Sanderson KV. Photosensitive dermatitis and renal tubular acidosis after ingestion of calcium cyclamate. Lancet 1969 ii 1273-1274. 

St. John s wort can canse photosensitization dermatitis therefore, the client shonld nse snnscreen when ontside. 

With chronic use, amiodarone may cause ventricular arrhythmias (mono-morphic or polymorphic ventricular tachycardia see p 14) or bradyanhyth-mias (sinus arrest, AV block). Amiodarone may cause pneumonitis or pulmonary fibrosis, hepatitis, photosensitivity dermatitis, comeal deposits, hypothyroidism or hyperthyroidism, tremor, ataxia, and peripheral neuropathy. 

Frain-Bell, W., A. Hetherington, and B.E. Johnson. 1979. Contact allergic sensitivity to chrysanthemum and the photosensitivity dermatitis and actinic reticuloid syndrome. Br. /. Dermatol. 101(5) 491-501. 

Skin reactions have been reported to occur in about 5% of patients treated with chlorpromazine (Byck 1975), although in other series the incidence is as low as 0.5% (Miller and Greenblatt 1976). Skin manifestations usually appear between the first and fifth week of treatment. Types of skin reactions include urticaria, maculopapular rash, petechial rash (due to vasculitis), erythema multiforme, photosensitivity dermatitis, and contact dermatitis. About 30% of individuals treated with moderate or large doses of chlorpromazine over a sustained period of time develop photosensitivity (Pillsbury and Caro 1966). Photosensitivity may be prevented or minimized by the use of suntan preparations containing p-amino-benzoic acid. Reports of an association of chlorpromazine with SLE (Becker 1973) are rare and if a true association exists, it must be extremely unusual. 

Abifadel R, Mortureiix P, Perromat M, Ducombs G, Taieb A (1992) Contact sensitivity to flavourings and perfumes in atopic dermatitis. Contact Dermatitis 27 43-46 Adams RM, Maibach HI (1985) A five-year study of cosmetic reactions. J Am Acad Dermatol 13 1062-1069 Addo HA, Ferguson J, Johnson BE, Frain-Bell W (1982) The relationship between exposure to fragrance materials and persistent light reactions in the photosensitivity dermatitis. Brit J Dermatol 107 261-274... 

Tokura, Y. 1998. Quinolone photoallergy photosensitivity dermatitis induced by systemic administration of photohaptenic drugs. 18 1-10. 

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