Use of 5-fluorocytosine in systemic candidiasis in infancy

Antifungals in systemic neonatal candidiasis

Fungal infections are common in the newborn period, especially among premature neonates, and are responsible for considerable morbidity and mortality. Currently, three classes of antifungals are commonly used in the treatment of systemic fungal infections in neonates: the polyene macrolides (e.g. amphotericin B [deoxycholate and lipid preparations]); the azoles (e.g. fluconazole); and the fluorinated pyrimidines (e.g. flucytosine). The echinocandins (e.g. caspofungin and micafungin) are a newer class of antifungals which shows promise in this population.The available kinetic data on amphotericin B deoxycholate in neonates are derived from very small studies and exhibit considerable variability. There are no kinetic data available for the use of lipid preparations in this population and, again, much has been inferred from adult studies. The information available for flucytosine is also limited but appears similar to what is observed in adults. Fluconazole has the most neonatal pharmacokinetic data, which show slightly less variability than the other antifungals. Genomic factors which affect the metabolism of amphotericin B and fluconazole may explain some of the observed variability. Most of the data for the efficacy of antifungal drugs in neonates are derived from retrospective studies and case reports. The data for amphotericin B deoxycholate and flucytosine are limited. There are more data for the liposomal and lipid complex preparations of amphotericin B and for fluconazole in this population. These support the use of these drugs in neonates, but because of their largely noncomparative nature they can not define the optimal dosage or duration of therapy. Amphotericin B deoxycholate is primarily nephrotoxic. It also induces electrolyte abnormalities and is to a lesser degree cardiotoxic. This toxicity in neonates appears similar to published data in older children and adults. While the lipid preparations of amphotericin B owe their existence to a presumed decrease in toxicity, the observed toxicity in neonates appears to be equal to that seen with the deoxycholate, although it should be noted that the lipid preparations are usually given at much higher dosages. Fluconazole toxicity appears to be milder and less frequent in this population than is seen with amphotericin B. In the final analysis, we do not have sufficient data to define the pharmacokinetic profiles, optimal dose or duration of therapy, or toxicity for any of these compounds in neonates. Further studies are necessary if the optimisation of antifungal therapy in this population is to continue.

An evolution of therapy for mucocutaneous candidiasis

Chronic mucocutaneous candidiasis is a relatively uncommon form of candida infection, and can be found in patients with primary deficiencies of their immune systems. When such infection occurs in patients with non-lethal immune deficiences defects of chemotaxis or cellular immunity can be found. In addition, significant endocrinopathies may occur, particularly involving the parathyroid and adrenal glands. A number of therapies have been devised for the treatment of chronic candidiasis, and have included both local and systemic medications. The most useful of these in the past have included the polyene antibiotics -- most notably, nystatin and amphotericin B. Antifungal activity has also been demonstrated clinically with the use of 5-fluorocytosine (a fluorinated pyramidine) and clotrimazole (a synthetic imidazole derivative). However, long-term therapy with medication has been required, and re-emergence of symptomatic infection has occurred when medications have been stopped. More recently, immune reconstitution with transfer factor has been employed in the treatment of patients who have been found to be anergic to candida. Such treatment in conjunction with chemotherapy has indicated that effective patient remissions can be obtained in those patients who develop and maintain cell-mediated immunity to candida. Twelve patients with chronic mucocutaneous candidiasis are profiled. Sites of involvement in the head and neck included the skin and hair (9), ears (9), nose (4) and throat (12). One patient had candida laryngitis, while five patients had evidence for esophageal disease. Of this latter group, one (a 5-year old boy) developed esophageal stenosis which required gastrostomy and retrograde esophageal dilatations. Nine patients were found to be anergic to candida. In these patients, systemic chemotherapy (as amphotericin B or 5-fluorocytosine) was used to induce remissions of disease and transfer factor was given to induce reactivity to candida. By so doing, topical or oral medications (utilizing miconazole, clotrimazole and nystatin) were found to suffice in maintaining effective local control of infection.

Candida albicans abscess of lung

Candida albicans lung abscess is a rare entity. We present a case in a patient who suffered from Hodgkin's disease and was receiving immunosuppressive therapy. The patient responded to treatment with 5-fluorocytosine.

Treatment of chronic muco-cutaneous candidiasis by lymphocyte transfer factor

A beneficial clinical effect from the administration of lymphocyte transfer factor is described in six patients with idiopathic early onset chronic muco-cutaneous candidiasis. Five patients in two families showed a familial disease pattern. Dermal anergy and failure to produce migratory inhibition factor with intact general immune function were found in patients tested. Antifungal chemotherapy was effective in clearing or markedly reducing the candidiasis and remission was maintained by repeated injections of transfer factor. Therapy was monitored using Candida skin test.

Septicaemia

Septicaemia still presents a major diagnostic and therapeutic challenge to the clinician. Most cases are hospital-acquiredand the reasons for their increasing prevalence are discussed, with reference to predisposing factors and opportunistic infections. The pathology and bacteriology of proven cases (positive blood cultures) in 1974 in a modern children's and maternity hospital complex are presented. Gram-positive and Gram-negative varieties are compared and the molecular biology and mechansims of endo- and exotoxaemia described. Successful therapy demands correct choice of antibiotic and the development of shock requires skilled supportive measures. For the former a rational scheme is outlined and a plea is made for collection of data for this purpose. Polypharmacy is deprecated and either an aminoglycoside or a cephalosporin forms the mainstay of therapy. The emergence of Bacteroids sp. in cases of abdominal and puerperal sepsis necessitates addition of a lincomycin or metronidazole. Superinfection with systemic candidiasis requires 5-fluorocytosine.

Endocarditis caused by Rhodotorula successfully treated with 5-fluorocytosine

A 7-year-old boy suffering from aortic regurgitation and mitral stenosis and regurgitation was admitted with endocarditis caused by Rhodotorula pilimanae and was treated successfully with orally administered antifungal agent, namely 5-fluorocytosine (5-FC). A dose of 100 mg per kg body weight, divided into four equal parts, was prescribed. After a prolonged febrile period his temperature dropped to normal on the fourth day of 5-FC therapy. Review of the published reports disclosed few cases of endocarditis due to Rhodotorula spp. and this case seems to be the first treated with 5-FC. Follow-up in one year, after discharge from the hospital, revealed no evidence of relapse.

Pulmonary candidiasis treated with 5-fluorocytosine

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