What are the management options for a patient with starvation ketoacidosis who has a vaginal culture positive for Group B Streptococcus (GBS) and is experiencing discomfort and itchiness?

From the Guidelines

For a patient with Group B Streptococcus (GBS) detected on vaginal culture, I recommend treatment with penicillin G 5 million units IV initial dose, then 2.5–3.0 million units every 4 hours until delivery, as outlined in the CDC guidelines 1. This approach is based on the most recent and highest quality study available, which prioritizes the use of penicillin G for GBS prophylaxis in patients who are not allergic to penicillin. The guidelines also provide alternative regimens for patients who are allergic to penicillin, including the use of ampicillin, cefazolin, or vancomycin, depending on the severity of the allergy and the presence of other medical conditions 1. Key considerations in the management of GBS infection include:

• The use of intrapartum antibiotic prophylaxis to prevent early-onset GBS disease
• The importance of obtaining vaginal-rectal swab for GBS culture and starting antibiotics for latency or GBS prophylaxis in patients with preterm premature rupture of membranes (pPROM) 1
• The need to discontinue GBS prophylaxis at 48 hours for women with pPROM who are not in labor, unless the results from a GBS screen performed on admission become available during the 48-hour period and are positive 1 While treating the starvation ketoacidosis remains the primary concern, addressing the GBS infection is important as it can cause significant vaginal symptoms and potentially lead to more serious infections, especially in a patient with metabolic derangements. GBS is typically sensitive to beta-lactam antibiotics, with penicillin being the first-line treatment. The initial IV therapy ensures rapid achievement of therapeutic levels, particularly important in the setting of ketoacidosis which may affect drug absorption. Once the patient is stabilized, transition to oral therapy can be completed as an outpatient if appropriate. It is essential to note that the management of GBS infection should be individualized based on the patient's specific clinical circumstances, including the presence of any allergies or other medical conditions.

From the FDA Drug Label

Treatment of all infections should be continued for a minimum of 48 to 72 hours beyond the time that the patient becomes asymptomatic or evidence of bacterial eradication has been obtained A minimum of 10-days treatment is recommended for any infection caused by Group A beta-hemolytic streptococci to help prevent the occurrence of acute rheumatic fever or acute glomerulonephritis.

The patient has Group B strep, not Group A. The FDA drug label for ampicillin does not provide specific guidance for the treatment of Group B strep.

In cases of β-hemolytic streptococcal infections, treatment should be continued for at least 10 days

The FDA drug label for clindamycin does provide guidance for the treatment of β-hemolytic streptococcal infections, but it is not clear if this applies to Group B strep. Therefore, no conclusion can be drawn from the provided drug labels regarding the treatment of Group B strep. 2 3

From the Research

Patient Diagnosis and Treatment

The patient has been diagnosed with starvation ketoacidosis and has also tested positive for Group B strep (GBS) from vaginal cultures due to complaints of discomfort and itchiness.

Group B Strep Infection

• Group B streptococcal infection is a significant cause of invasive disease in nonpregnant adults, with an annual incidence of 4.4 per 100,000 nonpregnant adults 4.
• The majority of adults with GBS infections have underlying diseases, including diabetes mellitus, malignant neoplasms, and liver disease 4.
• GBS infection can occur as an early onset or late-onset infection and has different treatment strategies, with antibiotics being effective in treating GBS infections at early stages 5.

Treatment Strategies

• High doses of benzylpenicillin (penicillin G) are recommended for the treatment of serious GBS infections 4.
• For patients allergic to beta-lactam agents, clindamycin may be a better alternative than erythromycin due to lower resistance rates 6.
• Vancomycin is administered in instances where patients are allergic to penicillin and second-line antibiotics are ineffective, although there have been reports of reduced susceptibility to vancomycin 7.

Antibiotic Resistance

• GBS is still recognized as being universally susceptible to beta-lactam antibiotics, but there have been reports of reduced susceptibility to beta-lactams, including penicillin, in some countries 7.
• Resistance to second-line antibiotics, such as erythromycin and clindamycin, remains high amongst GBS, with several countries noting increased resistance rates in recent years 7.