Tuesday, November 03, 2009

UTI Treatment and Birth Defects

The article in quotations has ben re-printed from the AUA Daily Scope.
"Study suggests UTI treatments may be associated with increased birth defect risk.

The Los Angeles Times (11/2, Dennis) "Booster Shots" blog reported, "Doctors assume antibiotics to be fairly safe during pregnancy." And, after analyzing "data on more than 13,000 women whose babies had birth defects, comparing their antibiotic use before and during pregnancy to that of almost 5,000 women whose babies didn't have birth defects," a team at the CDC found that the assumptions about safety were mostly accurate.

Specifically, "penicillins, erythromycins, and cephalosporins...were not associated with many birth defects," Medscape (11/2, Barclay) reported. On the other hand, two classes of drugs "were associated with several birth defects."

According to the paper in the Archives of Pediatrics and Adolescent Medicine, "mothers of babies with birth defects were more likely than mothers with healthy babies to report taking two types of antibiotics during pregnancy: sulfa drugs (brand names include Thiosulfil Forte and Bactrim) and urinary germicides called nitrofurantoins (brand names include Furadantin and Macrobid)," the AP (11/3, Johnson) reports. "Used for many decades, the antibiotics in question predate the Food and Drug Administration and its requirements for rigorous safety testing." Now, the agency "grades all drugs for safety to the fetus based on available research."

Such information, however, "is sorely lacking," HealthDay (11/2, Thomas) noted. "Much of that stems from the fact that ethical considerations preclude conducting drugs trials in pregnant women," explained lead investigator Krista Crider. Moreover, "resistant strains of bacteria are forcing doctors to use a wider array of antibiotics." As expected, the CDC team "found that about 30 percent of women took an antibiotic between the three months prior to conception and the end of the pregnancy."

MedPage Today (11/2, Peck) reported, "Sulfonamides were associated with six birth defects, more than any other class: anencephaly, two left-sided heart defects, hypoplastic left heart syndrome, and coarction of the aorta, choanal atresia, transverse limb deficiency, and diaphragmatic hernia." In addition, "four defects were associated with nitrofurantoin use: anophthalmia or microphthalmos, hypoplastic left heart syndrome, atrial septal defects, and cleft lip with cleft palate." "

I think this is a very important article.  Many doctors are either cavelier about giving antibiotics for presumed urinary tract infections or are unaware of the possibility that a positive urine culture or urine analysis might actually represent a contaminated urine specimen rather than a true urinary tract or bladder infection.  A contiminated specimen does not reauire treatment with an antibiotic while a true urinary infection in pregnancy does.
Urine specimens become contaminated due to improper collection technique.  In women, then urethra sits right next to the vagina and the labia.  When women void, the urine can touch the vagina, labia, and pubic hair that naturally contain bacteria and white blood cells (infection cells) and drag these cells into the specimen collection cup.  Often the result is a urine analysis that looks like an infection and a positive urine culture which in turn prompts the unsuspecting doctor to treat the the patient with antibiotics when in reality, the treatment was probably not necessary.
The better approach to the woman with a positive UA or urine culture is to simply ask her how she feels and is she has any urinary symptoms.  If she feels fine and has no symptoms, the doctor should suspect contamination and take further steps to prove that their is or is not an true urinary tract infection.  Further steps include either repeating the urine culture as either a clean catched mid-stream specimen or as a catheterized specimen. 
In a pregnant woman where the implications of antibiotic usage on the unborn baby are often unknown at best, I feel that the doctor has a special obligation to prove his or her choice to prescribe antibiotics.
Just think about this the next time the OB-Gyn prescribes an antibiotic for your "urinary infection."
Dr Schoor
Urologist Long Island