Chronic Spontaneous and Inducible Urticaria Associated With Mycoplasma pneumoniae Infection.

Acute childhood urticaria is a common disorder that has been associated with infections. In a few children, it may last for more than six weeks, thereafter it is characterized as chronic urticaria (CU). We report two cases, one suffering from chronic spontaneous urticaria and one chronic inducible urticarias (dermographism and cold urticaria). Both children had concomitant respiratory symptoms that were associated with Mycoplasma pneumoniae (MP) infection. Urticarias' symptoms and signs were refractory to regular antihistamines dose but showed marked improvement or complete resolution following clarithromycin administration. CU response to antibiotics pointed strongly to a potential causative role of MP in the pathogenesis of chronic spontaneous and chronic inducible urticarias. It is not clear if MP was the etiopathogenic cause or just the trigger. Nevertheless, refractory to antihistamines urticarias associated with MP infection may respond to antibiotics, which should be considered as an alternative therapeutic approach.

Allergy skin testing in predicting adverse reactions to fluorescein: a prospective clinical study.

PURPOSE: To evaluate allergy skin testing as a diagnostic tool of adverse reactions to fluorescein and whether allergy and previous sodium fluorescein angiography (SFA) act as predisposing factors. METHODS: Patients with adequate indication for fluorescein angiography and normal skin responsiveness were subjected to allergy skin-prick and intradermal tests for fluorescein, followed by SFA. During SFA, adverse reactions were monitored and classified as mild, moderate or severe. Previous SFAs and adverse reactions as well as the presence of atopy were also registered. RESULTS: One thousand and thirty-seven patients were enrolled in the study and 1284 SFAs were executed. Forty-four patients (4.3%) developed 55 adverse reactions; among them 50 (3.8%) were mild, three (0.2%) moderate and two (0.16%) severe. None of the reactors produced positive skin tests to fluorescein. Patients with atopy and previous SFAs were not more susceptible to adverse reactions. CONCLUSION: The vast majority of adverse reactions to fluorescein are mild and not attributed to immunological mechanisms. Allergy skin tests cannot predict non-immunological reactions but their utility remains substantial in predicting anaphylaxis during SFAs and must be performed in patients reporting risk factors in their past medical history.

Double-blind, crossover, placebo-controlled clinical trial with L-acetylcarnitine in patients with degenerative cerebellar ataxia.

Despite the different genetic defects underlying degenerative ataxias, it has been suggested that mitochondrial energy production and antioxidative metabolism dysfunction may be common biochemical alterations related to these diseases. Acetylcarnitine, a cholinomimetic substance, is involved in oxidative metabolism and is a potential source of acetyl groups for the synthesis of acetylcholine in the mammalian brain. To determine whether treatment with L-acetylcarnitine may improve some clinical conditions of patients with ataxia, a double-blind crossover study with L-acetylcarnitine was performed in 24 patients with degenerative cerebellar diseases. Patients were selected from an ongoing prospective follow-up study at the Department of Neurology at the University of Florence, Italy. Each treatment phase with L-acetylcarnitine or placebo lasted 6 months, after which patients were crossed over to the other treatment phase. Ataxia was documented and quantified with use of a clinical score. After the trial, we observed a statistically significant improvement of some symptoms and a slow progression of the disease in both groups of patients.

Abnormalities of mitochondrial enzymes in hereditary ataxias.

The activity of 7 mitochondrial enzymes, fumarase, NAD-malate dehydrogenase (MDH), citrate synthase (CS), valine dehydrogenase (VDH), succinate dehydrogenase (SDH), glutamate dehydrogenase (GDH), pyruvate dehydrogenase complex (PDHC) has been measured in platelet preparations from patients affected by Friedreich's ataxia (FA), dominant and non-dominant olivopontocerebellar atrophy (DOPCA, NDOPCA) and normal individuals. Significant decreases of GDH (P less than 0.01), PDHC (P less than 0.01), VDH (P less than 0.05) and SDH (P less than 0.05) activities were observed in FA patients. Significant decreases of GDH (P less than 0.01), PDHC (P less than 0.01), VDH (P less than 0.05), SDH (P less than 0.05) and CS (P less than 0.05) activities were Observed in ND-OPCA patients, whereas in DOPCA patients only GDH activity was significantly (P less than 0.05) decreased. In 8 of 10 patients with FA and in all patients with NDOPCA the activity of one or more of 4 enzymes, i.e. GDH, VDH, SDH, PDHC, was lower than the lowest of control values. Four of 6 patients with DOPCA had GDH activity lower than the lowest of control values. These results indicate that abnormalities of mitochondrial metabolism is a constant element in hereditary ataxia and suggest that the alteration primary leading to the different types of ataxias should be related to mitochondrial oxidative metabolism, at least at a regulatory level.

Energy metabolism in demented brain.

The term dementia refers to a number of very complicated disorders of the brain with several morphological, biochemical and functional alterations. Several alterations occur in Alzheimer's disease. They include alteration in neurotransmitters related substances and changes in brain metabolic rate. Changes in metabolic activity are among the earliest and best documented of all modification reported in Alzheimer's brain. They appear to be correlate with the severity of the disease, and to be more marked in specific areas of the brain which appear to be clinically more involved. In this report will be discussed the observations on changes of cerebral glucose metabolic rate, cerebral oxygen consumption, cerebral blood flow reported in vivo in demented patients. The observations of changes in energy metabolism related enzymes and the relationship between these changes and those in neurotransmitters related substances will be also reviewed.