Severe suppurative otitis media due to Streptococcus pneumoniae serotype 19A in a fully vaccinated infant by age

ABSTRACT

The routine use of pneumococcal conjugated vaccines (PCVs) in childhood has significantly reduced the frequency of invasive pneumococcal diseases (IPDs). Serotype replacement has occurred, resulting in an increase in nonvaccine serotypes. Despite this changing profile, both invasive and noninvasive cases continue to be seen with strains within the scope of PCV coverage. Although older children with comorbid disease are described as a risky group for vaccine insufficiency, vaccine failure patterns should be described in detail.

KEYWORDS:

• S.pneumoniae
• pneumococcal disease
• conjugated pneumococcal vaccine
• serotype 19A

To the editors,

Streptococcus pneumoniae is an important human pathogen that continues to focus attention worldwide. Pneumococcal infection spectrum ranges from mild respiratory infections such as otitis media and sinusitis to more severe diseases such as pneumonia, septicemia, bacteremia, and meningitis, called as invasive pneumococcal diseases (IPDs).¹ IPDs are among the most common causes of morbidity and mortality worldwide, especially among children under 5 years and among the elderly.² The widely and routine use of pneumococcal conjugated vaccines (PCVs) in childhood significantly reduced the frequency of IPD and has also led to changes in serotype distribution, leading to a renewed epidemiological profile.^2,3 However, with this changing profile, both invasive and noninvasive cases continue to be seen with strains within the scope of PCVs.⁴ Despite the high efficacy of PCVs, there is some evidence to support this fact regarding vaccine failure or vaccine breakthroughs.^5,6 In this context, we would like to share a recent case experience that can be interpreted as vaccine failure, from Turkey that has been regularly implementing PCVs in the national immunization program since 2008.

A previously healthy 8-month-old male infant was brought with complaints of fever, restlessness, and purulent discharge from ears. Cefixime therapy recommended by another center was discontinued by the family because of severe vomiting after two doses. On admission, the patient had a 39°C fever, pronounced restlessness, purulent discharge from both ears, hepatomegaly, and signs of dehydration. Bilateral perforation was present on the tympanic membranes and a sample was taken from the incoming discharge for culture. On hemogram analysis, white cell count was 26.62 × 10⁹/L, hemoglobin was normal, and an obvious thrombocytosis (1112 × 10⁹/L) was detected. C-reactive protein was 174 mg/dL. Aspartate aminotransferase (448 U/L), alanine aminotransferase (419 U/L), gama-glutamyl transferase (101 U/L), and lactate dehydrogenase (818 U/L) were noted as elevated, but bilirubin levels were normal. Coagulation tests did not deteriorate. There was hepatomegaly without a change in parenchymal echo on ultrasonography. Cefotaxime was started as initial therapy; however, teicoplanin was added since clinical and laboratory response could not be obtained after 48 h. With this treatment combination, the patient’s fever resolved, acute-phase reactants decreased, and purulent ear discharge ceased. No microorganism was detected in the blood culture, but the ear discharge sample yielded penicillin-resistance S. pneumoniae. Serotyping performed by the Quellung reaction at the national reference laboratory resulted in serotype 19A. Local or central nervous system complications associated with suppurative otitis media were not detected in advanced imaging. The patient was a fully vaccinated infant according to age (a total of three PCV13 doses is applied in Turkey—at the end of the 2nd and 4th months, and 12th month as a booster dose), and no immunodeficiency was detected. The patient was discharged after 14 days of systemic treatment without any sequela.

Although PCV13 vaccine insufficiency has often been described in children older than 60 months with underlying comorbidity,⁷ vaccine failure patterns should be described in detail with further studies since healthy children are at risk. Invasive and severe noninvasive cases—as in our case— with vaccine strains keep the importance of this issue on the agenda.