Introduction:
A case of pneumococcal mastitis in a breast-feeding mother 6 months postpartum is described. Mastitis is usually caused by Staphylococcus aureus . A review of the literature from 1950 to March 2018 revealed only four other cases in which the causative organism was Streptococcus pneumoniae .
Case presentation:
The nursing mother presented with high fever and the four cardinal signs of inflammation of the left breast: calor, dolor, rubor, tumour. In milk culture Streptococcus pneumoniae was isolated in numbers exceeding 105 c.f.u. ml-1 . The strain was of polysaccharide serotype 11 not included in Prevnar-13. Susceptibility testing showed full sensitivity to β-lactam antibiotics as well as to macrolides, lincosamides, vancomycin and tetracycline.
Conclusion:

Streptococcus pneumoniae should be considered as a possible causative agent of puerperal mastitis.