Iranian Journal of Pediatrics
Volume:13 Issue: 1, 2003

Recombinant DNA technology made it possible to produce biological drugs and pharmaceutical companies produced recombinant human drugs. There have been reports on the formation of antibodies against residual host cell protein. For this reason, it is important to check the patients sera for antibodies which could possibly be induced by recombinant drug it self and/or by contaminating proteins of the host cell. The present report refers to the obtainment of polyspecific antisera directed against Escherichia coli host strain used to produce recombinant human growth hormone. The antisera were obtained by the cascade immunization method. The animals (n=3 rabbits) were initially immunized with E. coli strain. The analysis of the antisera by dot blotting method showed a progressive recognition of the cascade method. These antisera were also used by ELISA methods. Results showed antibodies rising against E. coli polypeptide antigen.

Voiding dysfunction is a spectrum of abnormal learning of voiding behavior seen in 10-15% of children. Clinical symptoms are frequency, dysuria, urge incontinence or infrequent voiding. In some cases constipation is also seen. The complication is recurrent urinary tract infection with or without vesicoureteral reflux and probable renal insufficiency. For evaluation, urine analysis and urine culture, renal ultrasound and evaluation of urinary residue as well as voiding cystoureterography, renal DMSA scan and urodynamic study may be necessary.

Urinary tract infection is one of the most prevalent pediatric diseases which, if diagnosed and treated promptly, can lead to potential severe sequelae. Positive urinary nitrite is a sensitive test to determine urinary tract infection. In this study we evaluate the effect of delayed urinalysis on the result of urinary nitrite. We studied mid-stream clean catch urine of 30 children in Imam Sajjad Hospital of Yasouj University of Medical Sciences. Specimens stored at room temperature and urinary nitrite measured at 0, 0.5, 1 3 and 6 hours after collection. All specimens revealed negative urinary nitrite on beginning. 10% of specimens (3 cases) became nitrite positive between 30 minutes until 6 hours after collection. These false positive results of urinary nitrite were shown to have no relationship with urine culture and therefore no relativity to urinary tract infection. 3 reported positive cultures were not the same specimens with positive urinary nitrite and were related to non-nitrite positive organisms. We conclude that with passage of time after urine collection urinary nitrite may become falsely positive and lead to over-diagnosis of urinary tract infection. Therefore, all collected specimens must be transferred to laboratory as soon as possible to avoid false positive values.

Urinary tract infection (UTI) in children is usually treated with orally administered antibiotics for 7–10 days. Because of the unreliability of the patient compliance with the prescribed medications and because single-dose aminoglycoside therapy has been shown to be effective in adults with lower UTI, we conducted this retrospective study to asses efficacy of a single dose of gentamicin in patients with anatomically normal urinary tract, who had recurrent UTI. In this study 79 episodes of UTI in 43 patients treated with gentamicin (41 with single-dose and 38 with conventional method of 7-10 days). All patients, except 7 (2 in conventional therapy and 5 in single-dose group), received both methods of therapy in different episodes of infection. Isolated organisms from patients in single-dose group consisted of E. coli (90.4%), Klebsiella (7.3%), and miscellaneous bacteria (2.3%). In conventional therapy group E. coli (87%), Klebsiella (5.2%), and miscellaneous bacteria (7.8%) were isolated. E. coli was the most frequently isolated microorganism in both groups and sensitive to given antibiotics with no exception. 90.26 % of urine cultures were negative in single-dose group and 94.3 % in conventional therapy group 48-72 hours after treatment, the difference was statistically not significant (p=0.36). Cumulative recurrence rate was 56 % in single-dose and 48.6% in conventional therapy group 6 weeks after treatment with no significant difference (p=64%). Relapse rate (recurrence of the same organism and the same sensitivity as for the therapy begin) 6 weeks after treatment) was 57.3 % in single-dose and 33.5 % in conventional therapy group. This difference was also statistically not significant (p=26%). No side effects could be detected in patients who had been treated with single-dose. The results of the study allow the conclusion that in the absence of urinary tract malformations a single-dose treatment of UTI in children will be effective enough.

Air pollution is a major problem in Tehran. Most important agents responsible for the high pollution include carbon monoxide, sulfur dioxide, nitrogen dioxide, hydrocarbons and suspended particles. Determination of quality and quantity of polluting agents is of great importance for sustaining the inhabitants health level. We studied carbon monoxide, one of the most hazardous air-polluting agents, in 22 urban districts of Tehran. The results showed that in average 4.39% of the air in Tehran has a CO concentration of 15-30 ppm. The 12th district with 17.99% and 11th district with 16.43% had the highest pollution of carbon monoxide. 6th and 7th districts had 11.22% and 9.5% respectively. The lowest level of pollution was found in 21st district (0%) and 1st district (0.11%). Variance analysis of districts of Tehran showed that there is a significant relation between mean air pollution of 11th and 12th districts and other districts.