Roxithrornycin in chlamydial infections 
Clinical study 
EV ALUATION OF ROXITHROMYCIN 
IN THE TREATMENT OF UROGENITAL 
CHLAMYDIAL INFECTIONS 
M. Potočnik and H. Hren-Vencelj 
ABSTRACT 
Background. Chlamydia trachomatis infections represent the most frequent sexually transmitted disease in 
developed countries and probably also worldwide. In women the inflammation may spread to involve the 
intemal reproductive organs, which may lead to extrauterine pregnancy and tubal infertility. 
Methods. Twenty patients (15 men and five women) with proven chlamydial infection of the lower 
urogenital tract were treated with the macrolide antibiotic roxithromycin in a single daily dose of 300 mg for 
10 days. Before the treatment, the causative organism was detected with a direct immunofluorescent method 
in swab specimens collected from the urethra and/or cervical canal. The test was repeated after the treatment. 
Results. Microbiological cure was achieved in 19 patients (95% ), and clinical symptoms disappeared in ali 
20 patients studied (100% ). 
KEY WORDS 
Chlamydia trachomatis, urogenital infections, roxithromycin 
INTRODUCTION 
Infections with Chlamydia trachomatis represent 
the most frequent bacterial sexually transmitted disease 
in developed countries and probably also in the 
entire world. Every year about 500 million individuals 
are infected ali over the world, and between five 
and six million new cases occur in the United 
States (1 ). Urogenital infections, predorninantly 
urethritis and epididymitis in men and urethritis 
and/or cervicitis and salpingitis in women, are caused 
by C. trachomatis serotypes D to K. 
The infection is transmitted mainly by sexual 
contact (2, 3) and rarely from the genitalia to the 
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eyes or vice versa. It occurs in young sexually active 
persons, mostly between 15 and 35 years of age. Up 
to 70% of women and up to 20% of men have no 
symptoms (4) . The clinical manifestations in men 
include dysuria with different forms of discharge; 
complications such as prostatis, epididymitis and 
proctitis are uncommon. Symptoms in women are 
described in extenso in the manuscript by Vrtačnik­
Bokal et al. 
In our study we tried to evaluate the macrolide 
antibiotic roxithromyc:in (Renicin, LEK Pharmaceuticals 
and Chemicals d.d. Ljubljana) administered on an 
out-patient basis. We selected roxithromycin beca~se 
it has the greatest bioavailability among macrolides 
127 
Roxithromycin in chlamydial infections 
and a long elimination half-life, attains high plasma 
concentrations and shows excellent tissue penetration. 
The drug achieves high concentrations at the site of 
the infection (5), yet with no cumulation. 
PATIENTS AND METHODS 
We studied patients with a clinical diagnosis of 
urethritis and/or cervicitis attending the out-patient 
clinic for sexually transmitted diseases at the 
Department of Dermatology, University Medica! Centre 
Ljubljana. To establish the aetiology of the in-
flammation, swab specimens collected from the urethra 
and/or endocervix were first examined for the presence 
of gonococci (staining by Gram's method and 
methylene blue) and trichomonads. A chlamydial 
aetiology was demonstrated with the use of the C. 
trachomatis Direct Specimen Test (Syva MicroTrak). 
All specimens were tested directly after collection. 
According to the manufacturer's instructions, specimens 
containing at least 10 chlamydial elementary bodies 
were assessed as positive. Positive and negative 
control slides were used to verify each result. 
Roxithromycin therapy was administered only to 
patients with a proven chlamydial inflammation. The 
test results were available within one hour and the 
treatment was started immediately. Roxithromycin 
was given in a single daily dose of 300 mg (2 
tablets of 150 mg each) for 10 days to a total of 
3000 mg. 
On follow-up examination at the end of treatment, 
a control urogenital swab specimen was obtained 
from each patient and examined by the same methods 
as prior to treatment. 
RESULTS 
On initial evaluation, a chlamydial infection was 
diagnosed in 15 men and in five women. The 
average age for the men was 30.7 years, for the 
women 28 years, and for the group as a whole 30.7 
years, corresponding to the period of greatest sexual 
activity (Tab. 1 ). 
An acute inflammation was established in 16 patients 
while four had a recurrence. Five patients had been 
treated previously without success, two with penicillin 
antibiotics, one with trimoxazole and two with 
doxycycline, which had been discontinued because 
of gastrointestinal side effects in one patient and 
had proved ineffective in the other. 
On completion of the treatment, examination of 
128 
Tab. l. Patient characteristics. 
Sex % Mean age 
(years) 
Males 15 75 30.7 
Females 5 25 28.0 
Total 20 100 30.1 
the urethra and/or cervical canal for C. trachomatis 
was negative in 19 patients and positive in one. Ali 
20 patients were free of symptoms. 
DISCUSSION 
Severa! effective chemotherapeutic agents, among 
them also macrolides, are available on the market 
for the treatment of sexually transmitted chlamydial 
infections. Microbiological and clinical data indicate 
that erythromycin is not always effective and is 
often poorly tolerated when given in larger doses. 
Compared to erythromycin, the newer macrolides, 
roxithromycin being one of them, are at least as 
effective in vitro and in vivo for the treatment of 
chlamydial urethritis and cervicitis, but they have 
the advantage that they can be given in a single 
daily dose for a shorter period of tirne (8,9). 
Tab . 2. Oinical and bacteriological cure rate 
Oinical cure rate 
Bacteriological cure rate 
20 
19 
100% 
95% 
Since chlamydial infection in women is the leading 
cause of tubal infertility and extrauterine pregnancy 
in the developed world (10), correct, timely diagnosis 
and effective treatment of these infections in women 
and their partners are extremely important. 
The clinical and bacteriologic efficacy of roxi-
thromycin in our patients can be assessed as very 
good; the pathogen was eradicated in 19 patients 
and ali 20 patients were free of symptoms at the 
end of treatment. Side effects in the form of 
diarrhoea and abdominal pain occurred in one patient 
only and were mild. 
Our results agree with the literature reports (11,12) 
in showing that roxithromycin given in a single daily 
dose of 300 mg for 10 days is an effective antibiotic 
with minimal side effects for the treatment of sexually 
transmitted chlamydial infections of the urogenital 
tract. 
acta dermatovenerologica A.P A. Vol 4, 95, No 3 
Roxithromycin in chlamydial infections 
CONCLUSIONS 
The macrolide antibiotic roxithromycin is suitable 
for the treatment of chlamydial genitourinary 
infections. It is equally effective as other antibiotic 
agents in use. 
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l. Stamm WE. Chlamydia trachomatis genitourinary 
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9 .Pechere J C. Oinical evaluation of Roxithromycin 
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10. Hay PE, Thomas BJ, Homer PJ et al. Chlamydia 
trachomatis in women: the more you look, the 
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11. Lassus A, Seppala A. Roxithromycin in non-
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AUTHORS' ADDRESSES 
Marko Potočnik MD, DMD, Dpt. of Dermatology, Oinical Centre 
Zaloška 2, 61000 Ljubljana, Slovenia 
Helena Hren-Vencelj PhD, Professor of microbiology, Institute of microbiology 
Medica! Faculty, 61000 Ljubljana, Zaloška 4, Slovenia 
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