Case study: Genital swelling following caesarean delivery

A presentation of clitoral swelling and vaginal discharge at three weeks post-caesarean section led to a diagnosis of infection with group A streptococci.

Coloured transmission electron micrograph of group A Streptococcus bacteria
Coloured transmission electron micrograph of group A Streptococcus bacteria

A 36-year old woman presented in the surgery, three weeks post-partum, with complaints of vaginal discharge and swelling in the clitoral region. She had delivered by caesarean section, with the indication for this being previous caesarean delivery.

The post-operative period was uneventful for the mother but the baby showed signs of infection and required admission to the special care baby unit. The neonatal CRP was raised and intravenous antibiotics were administered for seven days. The baby recovered and both mum and baby were discharged on the seventh post-operative day.

At presentation, the patient was apyrexial, but genital examination showed clitoral swelling with vaginal discharge (not offensive, discoloured or itchy). The mother had not been swabbed postnatally as no conclusive cause of the baby's infection had been found.

A high vaginal swab was taken and sent for culture and sensitivity. Since there were no clinical signs of sepsis, apart from vaginal discharge and genital swelling, she was advised to ring the surgery for the results of the swab culture.

Microbiologists contacted the surgery 20 hours later, as the swab confirmed heavy growth of Group A Streptococcus.The GP contacted the patient urgently.

She was clinically well with no known allergies. As advised by the microbiologist she was treated with oral amoxicillin. The baby was well, had already been treated with antibiotics in the neonatal period, and was kept under observation. The GP discussed the red flag symptoms of sepsis with the mother.

Both mother and baby were reviewed again in the surgery one week later. The caesarean wound had healed well and the genital swelling had settled. The baby was also clinically well with no signs of sepsis.

The outcome would have been very different if the patient had not been seen the same day as a matter of urgency, and the swab had not been taken.

Streptococcal infections

Streptococci are Gram-positive cocci, spherical or ovoid in shape and tend to form chains with each other. Streptococci that cause human infections are usually facultative anaerobes, preferring lower levels of oxygen in their environment.

Streptococci are further classified in to subtypes based on sugar chains expressed on their outer shell (Lancefield group) and their behaviour when grown in the lab (alpha or beta haemolysis).

Most streptococci causing skin infections belong to Lancefield groups A, C and G and are beta-haemolytic.

Group A Streptococcus (GAS)

Most infections caused by Group A are minor: scarlet fever, impetigo, cellulitis, sinusitis, middle ear infection, soft tissue infection, pharyngitis or tonsillitis. People may carry GAS in the throat or on the skin and have no symptoms of illness.

Most people with minor GAS infections make a full recovery with no long term problems. There is a small risk of rheumatic fever and glomerulonephritis in patients with severe symptoms if infection spreads and left untreated.

These bacteria are spread through direct contact with mucus from the nose or throat of an infected person, or through skin contact with an infected wound. GAS can be transmitted environmentally through contact with contaminated objects such as towels or bedding, and through ingestion of food contaminated by a carrier.1

Group A can cause severe or life threatening infections - pneumonia, sepsis or meningitis - in people with a weak immune system especially people with diabetes, the terminally ill, those with HIV infection, the elderly or babies. These patients should be treated promptly with antibiotics.

Two of the most severe forms of invasive GAS disease are necrotising fasciitis and streptococcal toxic shock syndrome (STSS). STSS occurs when bacteria release toxins in the blood which can result in high temperature, and a fall of blood pressure resulting in dizziness and confusion.

Invasive GAS infection and scarlet fever are both notifiable diseases2 . Health professionals must inform local health protection teams of suspected cases.

GAS and puerperal infections

Puerperal infections cause morbidity in 5-1% of all pregnant women. GAS is an historically important cause of puerperal infections and sepsis.

Despite preventative measures including antibiotic use and improved hospital sanitation, GAS infections are re-emerging world wide and remain the most common cause of severe puerperal infections and death world-wide.3,4 When associated with STSS, mortality rates approach 30-50%.5

Predisposing factors

Predisposing factors6 include:

  • Mode of delivery (vaginal/caesarean section)
  • Antibiotic administration during labour or delivery
  • Delayed diagnosis
  • Disrupted mucosal barriers
  • The location where delivery or labour occurred
  • Exposure to GAS carriers
  • Altered vaginal pH from amniotic fluid exposure
  • Altered immune status associated with pregnancy
  • Genetic background of the host
  • Highly specialised immune responses associated with the female reproductive tract

Route of maternal infection

GAS can be found in the normal female reproductive tract but its colonisation is considered to be very rare and its presence alone is not sufficient to cause infection.

The host and microbial factors that influence infection remain unresolved but it is apparent that pregnant and postpartum women are predisposed to bacterial infections in general.7 Mothers with a recent history of sore throat succumb to GAS, suggesting that these women infect themselves after delivery through contamination of the perineum.

Another cause of GAS exposure is through interaction with children in the house or at work place. Caesarean section is the single most important risk factor for postpartum maternal infection in a hospital and this could be due to various factors of which the most important one is invasive nature of the surgery.8

Regardless of the type of delivery, postpartum patients have a 20-fold increased incidence of GAS compared to non-pregnant women. The mechanism behind GAS and postpartum susceptibility remain poorly understood.

Puerperal infections present rapidly within 24-48 hours postpartum and can be non specific or invasive infections in the form of endometritis, necrotising fasciitis or STSS.

Clinical presentation

The typical clinical presentation5 is:

  • Fever or rigors
  • Uterine pain
  • Malodorous vaginal discharge

Atypical presentation may involve:

  • Nausea or vomiting
  • Swelling or pain in the extremities
  • General malaise
  • Myalgia
  • Headaches
  • Dyspnoea
  • Rash
  • Pharyngitis
  • Confusion
  • Non-foul smelling vaginal discharge.


FBC, ESR, CRP and blood cultures may facilitate diagnosis. In secondary care, endometrial aspiration in addition to blood cultures may be a useful rapid diagnostic tool.5

Primary care management

Post-partum patients with a history of vaginal discharge, feeling unwell or genital swelling should be seen the same day, as a matter of urgency. General examination should include temperature and BP. Conduct a pelvic examination: a high vaginal swab must be taken.

Speak with the microbiologist on call or obstetrician if in doubt, and treat urgently if clinically indicated. Penicillin is the first-line drug for treatment, or clindamycin for those who are allergic to penicillin.

Admit the patient if there is any suspicion of sepsis. Invasive infection is treated with IV antibiotics, fluid and source control. Source control may require extensive wound or vulval debridement, hysterectomy or combination of these.5 The use of IV immunoglobulins in STSS is controversial.


The RCOG recommends that all clinicians should be aware of symptoms and signs of sepsis and the potentially lethal course that it can take in a short period of time. However, the symptoms and signs can be subtle, as in this patient. A high index of suspicion for sepsis has to be maintained, especially in postpartum patients, with early investigations to rule out sepsis.

This patient was systemically well and could be treated as an outpatient, but often inpatient care is needed and patients are best managed with multidisciplinary team input, to optimise the outcome.

Caesarean delivery is reported to be one of the risk factors for puerperal sepsis.9 Common organisms responsible for puerperal sepsis include Group A Streptococcus, E Coli, Staphylococcus aureus, Streptococcus pneumoniae, MRSA, Clostridum difficile and Morganella morgannii.9

Delay in recognition and treatment can significantly raise the morbidity and mortality risks.10

  • Dr Sharma  is a GP in Oldham and clinical director of Oldham CCG; Dr Tandon is a GP in Oldham

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  1. Public Health England The characteristics, diagnosis and management of group A streptococci infections. July 2014
  2. Public Health England Notifications of infectious diseases. July 2014
  3. Castagnola DE, Hoffman MK, Carlson J et al et al. Necrotizing cervical and uterine infection in the postpartum period caused by group A streptococcus. Obstet Gynecol 2008;111:533-5
  4. Stevens DL et al. Severe group A streptococcal infections associated with toxic shock like syndrome and scarlet fever toxin A. The N Engl J Med 1989:321 91): 1-7
  5. Anderson B. Puerperal Group A Streptococcal Infection. Obstetrics & Gynecology, 2014; 123: 874-82.
  6. Masson KL, Aronoff DW. Postpartum Group A streptococcus Sepsis and maternal immunology. Am J Reproductive Immunology 2012;67:91-100
  7. Mor G, Cardenas I. The immune system in pregnancy: a unique complexity. Am J Reprod Immunol. 2010; 63 (6):425-33.
  8. Chuang I et al. Population based surveillance for postpartum invasive group A streptococcus infection. 1995-2000. Clin Infect Dis 2002;35 (6):665-70
  9. Maternal sepsis (Puerperal fever) due to Group A Streptococcus. Information for clinicians. Government of New South Wales, Australia. Update June 2012.
  10. Sepsis following pregnancy, bacterial. Royal College of Obstetricians and Gynecologists. Green Top Guidelines No 64b. 2012

Photo: J.L. Carson, Custom Medical Stock Photo/Science Photo Library

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