[Primary infection with varicella-zoster virus in risk groups]

Chickenpox represents the primary form of Varicella-zoster virus (VZV) infection and appears most commonly in preschool and school children. The clinical course of chickenpox in immunocompetent children is mainly mild and complications are rare (1-5). Adults and immunocompromised patients are considered to be risk groups for development of serious and even life-threatening complications. The most frequent bacterial complications include secondary bacterial skin infections, angina, sinusitis, otitis and bronchopneumonia. Central nervous system complications, visceral dissemination, pneumonitis and myocarditis are the major viral complications (6,7). Acyclovir is approved for treatment of chickenpox in risk groups to reduce the frequency of viral complications and to treat those ones which have already appeared (7,8). The treatment of bacterial complications is based on the examination results of the bacterial sensitivity to antibiotics.

In our study patients with the diagnosis of chickenpox based on the history of disease, clinical features and clinical course and data on intimate contact with individuals suffering from chickenpox, were clinically followed-up. Sedimentation rate, blood count and urine samples were analyzed. A unique questionnaire was designed to follow-up the following data: sex, age, course of the disease, occurrence of complications in immunocompetent patients and those belonging to risk groups and effects of acyclovir therapy.

During a three-year period 48 patients with chickenpox treated at the Clinic of Infectious and Dermatovenereology Diseases have been observed. 64.6% of them were males and 35.4% were females. 29.2% were infants under 1 year of age, 29.2% were 2-13 years of age and 41.6% were 14-50 years of age. According to the clinical course, patients were divided into two groups: the first one included patients who developed complications of chickenpox (54.1%), the second one consisted of those without complications (45.1%). 72.7% of all complications occurred in patients belonging to risk group (14-50 years of age). Among viral complications in risk groups the most common were pneumonia (44.4%) and haemorrhagic rash (44.4%), only one patient (11.1%) developed a mild, viral meningitis. Bacterial complications were also present in risk group as secondary bacterial skin infections (71.4%) and otitis media (28.6%). Viral complications were treated successfully by 750 mg intravenous acyclovir given 3 times a day, or by 800 mg oral acyclovir given 5 times a day during 7-10 days. Adequate antibiotics were used in the treatment of bacterial complications. A case of chickenpox associated with the meningitis caused by Haemophilus influenzae was also reviewed.

In this study the majority of observed patients had a mild, clinical form of chickenpox that is in accordance with the other available clinical data (1-4). Complications developed more frequently in the adults and usually were of viral etiology. All patients were on time treated with acyclovir and visceral dissemination did not occur in any of them. Complications had a favourable evolution and VZV meningitis was healed without sequelae. Many authors have written about successful use of acyclovir in the treatment of chickenpox. However, acyclovir is not recommended to immunocompetent persons without chickenpox viral complications who do not belong to risk groups (1,3,4,9-11).

Our findings lead to the conclusion that chickenpox in adults may have an uncertain outcome because of a more severe clinical course and susceptibility to complications. In our study application of acyclovir in that age group provided good results as for prevention and treatment of complications of chickenpox if already manifested.