Fluconazole susceptibility and strain variation of Candida albicans isolates from HIV-infected patients with oropharyngeal candidosis.

Over a 16 month period we conducted a prospective study in a cohort of 45 HIV-positive patients to detect the development of resistance to fluconazole and to analyse the epidemiology of oropharyngeal candidosis (OPC). Each episode was treated with fluconazole 100 mg/day po for 10 days. All yeast isolates were tested for their in-vitro susceptibility to fluconazole. Multiple strains of Candida albicans simultaneously isolated from a given patient were typed by electrophoretic karyotyping. Overall, 106 episodes of OPC were diagnosed among the 45 patients: 18/45 patients (40%) had only one episode, 11/45 (24%) had two episodes, and the remaining 16/45 (36%) had three or more episodes (range 3-7). Cure (complete resolution of signs and symptoms and negative post-treatment cultures) and improvement (complete resolution of signs and symptoms but positive post-treatment cultures) were observed in 30/106 (28%) and 69/106 (65%) episodes of OPC, respectively. Failure (absence of improvement or exacerbation of signs and symptoms) was observed in seven episodes (7%) from four patients. In two of these four patients a significant and progressive increase in fluconazole MICs was observed: from 0.25 to 16 mg/L in one patient, and from < or = 0.125 to 32 mg/L in the second one. Tests on multiple colonies from individual isolation plates showed that it was not unusual to obtain different fluconazole MICs, indicating that, in order to avoid misleading results, one should perform in-vitro susceptibility testing by using a multiple colony inoculum rather than an inoculum made from a single colony. A total of 213 strains of C. albicans isolated from seven patients who suffered from four or more episodes of OPC through the course of the study were typed by electrophoretic karyotyping. Five individuals (71%) were infected with yeasts with only one DNA type, while the other two patients showed the presence of two or three different DNA types. The simultaneous presence of multiple types was found only in one of the seven subjects. Our data confirm the efficacy of fluconazole 100 mg/day for the treatment of OPC in HIV patients. Isolation of fluconazole-resistant strains of C. albicans with this regimen is rare. The vast majority of HIV patients are infected with a unique strain of C. albicans throughout each episode of infection. A minority of patients, however, can harbour strains of C. albicans with variable patterns of fluconazole susceptibility simultaneously.

[Observations about the treatment of Cytomegalovirus retinitis in patients with HIV infection using Ganciclovir and Foscarnet] / Osservazioni relative al trattamento con Ganciclovir e Foscarnet della retinite da Cytomegalovirus in pazienti con infezione da HIV.

Objective: The Authors report their experience of Cytomegalovirus (CMV) retinitis therapy in HIV patients, using Ganciclovir and Foscarnet in monotherapy. They also evaluate the reliability of the Polymerase Chain Reaction (PCR) through the qualitative technique as an index of active disease. Methods: 18 patients suffering from CMV retinitis were treated: Ganciclovir was administered at a dosage of 10 mg/kg b.w./day and Foscarnet at 180 mg/kg b.w./day, both of them for 21 days during the induction phase. During the mantainance phase the former was administered at 5 mg/kg b.w./day and the latter at 90 mg/kg b.w./day for 5 days a week. Results: Both the drugs induced the stabilization or regression of the lesions. There was however a relapse with both therapies. We did not observe a significant difference either in the entity and the duration of the stabilization or in the survival from diagnosis time. Finally the PCR method was not helpful in the diagnosis of CMV retinitis.