Caffeine diagnosis

Caffeine is a strong activator of CICR it sensitizes RyR to activating Ca2+ and increases the maximum attainable level. Because high concentrations (>mM) of caffeine effectively discharge Ca2+ from the Ca2+ store, it is frequently used for experimental evaluation of functional occurrence of RyRs. Caffeine is used for diagnosis of MH muscles biopsied from MH patients contract by a lower dose of caffeine than normal human, due to an enhanced CICR activity (see Disease)./Para>... 

Mackenzie, A.E., Allen, G., Lahey, D., Crossen, M.L., Nolan, K., Mettler, G., Worton, R.G., MacLen-nan, D.H., Korneluk, R. (1991). A comparison of the caffeine halothane muscle contracture test with the molecular genetic diagnosis of malignant hyperthermia. Anesthesiology 75,4-8. 

A formal diagnosis of substance dependence requires a maladaptive pattern of abuse that leads to clinically significant impairment or distress. More detailed criteria revolve around the development of tolerance, the experience of withdrawal when abstinence is required, the inability to stop using the drug, and continued use over a protracted period of time. The question is whether or not these criteria, clearly applicable to cocaine, heroin, and other drugs, are met by caffeine. 

The symptoms of jitters, insomnia, tremors, and agitation are common in those consuming caffeine and in those with depression or the other illnesses for which these drugs are prescribed. Combining caffeine with antidepressants may exaggerate the symptoms and make it difficult for the physician to arrive at an accurate diagnosis or evaluate the drug s effectiveness. 

I. lancu A. Olmer R. D. Strous, Caffeinism History, Clinical Features, Diagnosis, and Treatment. In Caffeine and Activation Theory) B. D. Smith, U. Gupta, B. S. Gupta, Eds. CRC Press LLC Boca Raton, FL, 2007 pp 331-347. 

Caffeine intoxication is the only official diagnosis associated with caffeinism in the DSM-IV-TR. Caffeine-induced anxiety may manifest as restlessness, nervousness, excitement, insomnia, diuresis, flushing, gastrointestinal disturbance, muscle twitching, irritability, and jitteriness. If caffeine-induced insomnia requires specific treatment, caffeine-induced sleep disorder (DSM-IV-TR) is an appropriate diagnosis." ... 

Several medical, medication-induced, or substance-related causes of mania and depression have been identified (see Table 68-2 for causes of mania and Table 67-1 in Chap. 67 on depressive disorders for causes of depression). " A complete medical, psychiatric, and medication history physical examination and laboratory testing are necessary to rule out any organic causes of mania or depression. An accurate diagnosis is important because some psychiatric and neurologic disorders present with manic-like symptoms. For example, attention-deficit/hyperactivity disorder and a manic episode have similar characteristics thus individuals with bipolar disorder may be misdiagnosed and prescribed central nervous system stimulants. Use of any substance that affects the central nervous system (e.g., alcohol, antidepressants, caffeine, central nervous system stimulants, hallucinogens, or marijuana) can worsen symptoms and decrease the... 

IV. Diagnosis is suggested by the history of caffeine exposure or the constellation of nausea, vomiting, tremor, tachycardia, seizures, and hypokalemia (also consider theophylline see p 354). 

Uric acid and xanthines are markers for metabolic disorders such as gout, Lesch—Nyman syndrome, and xanthinuria. Measurements of urinary excretion of purine metabolites, among them uric acid and xanthine, have been proposed as a marker for microbial protein synthesis. Their simultaneous determination is useful for diagnosis and treatment of hyperuricemia. In addition to xanthine and hypoxanthine, notable members of the xanthine class include caffeine, theophylhne, and theobromine. ... 

The observation that sensitive subjects are more likely to have trembling hands is considered to be a CNS effect and not a direct effect on muscle. Caffeine doses higher than 15mgkg induce headaches, jitteriness, nervousness, restlessness, irritability, tinnitus, muscle twitchings, and palpitations. These symptoms of chronic excessive caffeine intake are part of the criteria used to make the diagnosis of caffeinism. The same symptoms have been reported in adults on abrupt cessation of caffeine use. 

Because of the bronchial muscle relaxant effect, caffeine is used in chronic obstructive pulmonary disease and for the treatment of asthma. The use of caffeine in the treatment of children with minimal brain dysfunction, to increase the duration of electroconvulsive therapy-induced seizure, for allergic rhinitis, as well as for atopic dermatitis has also been described. Recently, caffeine has been used as a diagnostic test for malignant hyperthermia and in the diagnosis of neuroleptic malignant syndrome, a complication of neuroleptic therapy. 

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