From the Guidelines
The presence of Beta-hemolytic Streptococcus group B (GBS) in a urinalysis is a significant finding that requires prompt attention, particularly in pregnant women, as it increases the risk of preterm labor and neonatal infection. The significance of GBS in urinalysis lies in its potential to cause urinary tract infections (UTIs) and its implications for pregnancy outcomes. According to the Centers for Disease Control and Prevention (CDC) guidelines 1, GBS bacteriuria in pregnant women is a marker for heavy genital tract colonization and increases the risk of early-onset GBS disease in newborns.
Key Considerations
- GBS is found in the urine of 2%–7% of pregnant women 1
- Maternal GBS bacteriuria is associated with an increased risk for early-onset disease in the newborn 1
- The CDC recommends universal screening for GBS colonization at 35–37 weeks’ gestation and intrapartum antibiotic prophylaxis for women with GBS colonization or other risk factors 1
Treatment and Management
- Treatment of GBS UTIs typically involves antibiotics, with penicillin being the first-line option 1
- For uncomplicated UTIs, amoxicillin 500 mg three times daily for 5-7 days is often prescribed
- For those with penicillin allergies, alternatives include cephalexin 500 mg four times daily, or clindamycin 300 mg four times daily for the same duration
- Intrapartum chemoprophylaxis is recommended for women with GBS colonization or other risk factors, with penicillin G being the preferred agent 1
Special Considerations in Pregnancy
- Pregnant women with GBS in their urine require treatment regardless of symptoms 1
- GBS colonization during pregnancy increases the risk of preterm labor and neonatal infection
- The CDC recommends routine screening for asymptomatic bacteriuria in pregnant women, which can help identify those with GBS colonization 1
From the Research
Significance of Beta-hemolytic Streptococcus (BHS) group B in Urinalysis
- Beta-hemolytic Streptococcus (BHS) group B, also known as Group B Streptococcus (GBS), is a significant cause of urinary tract infections in pregnant women 2, 3.
- GBS can cause chorioamnionitis, endometritis, and urinary tract infections in pregnant women, which can lead to severe consequences for both the mother and the newborn 2.
- The presence of GBS in the urine can indicate colonization, which is associated with an increased risk of early-onset neonatal infections (EOD) 4.
- Studies have shown that GBS colonization of the genital tract among pregnant women is diagnosed between 35 and 37 weeks of gestation, and is associated with approximately 25% risk of neonatal early-onset infections (EOD) 4.
Risk Factors and Prevention
- Risk factors for GBS infection include fever during labor, rupturing of membranes more than 18 hours before delivery, prematurity, and chorioamnionitis 2, 5.
- Intrapartum antibiotic prophylaxis is recommended for GBS-colonized women to reduce the risk of early-onset neonatal GBS infection 6, 2, 5.
- Penicillin G is the antibiotic of choice, while penicillin A (ampicillin or amoxicillin) is an alternative 6, 5.
- In case of penicillin allergy, erythromycin or clindamycin are generally active against Group B streptococci and carry no particular risks for the infant 6, 5.
Antibiotic Resistance
- Studies have shown that GBS isolates are becoming increasingly resistant to macrolides and lincosamides, highlighting the need for regular supervision of drug sensitivity 4.
- Inducible MLSB resistance to erythromycin and clindamycin was found in 23.1% and 10.7% of the isolated strains, respectively 4.
- Constitutive MLSB resistance was detected in 14.9% of the cases 4.