Kingella are gram-negative organisms that colonize the human oropharynx. They cause skeletal infections, endocarditis, bacteremia, and, rarely, pneumonia, epiglottitis, meningitis, abscesses, and ocular infections. Diagnosis is by culture. Treatment is with antibiotics.
Kingella, which belong to the family Neisseriaceae, are short, nonmotile, facultative, gram-negative coccobacilli that occur in pairs or short chains. The organisms are slow-growing and fastidious. Kingella are recovered from the human oropharynx and are a rare cause of human disease.
Among Kingella species, Kingella kingae is the most frequent human pathogen; these organisms frequently colonize the mucous membranes of the oropharynx. Children aged 6 months to 4 years have the highest rates of colonization and invasive disease from this pathogen. K. kingae is transmitted from child to child through close personal contact (eg, at day care centers). Infection has a seasonal distribution, with more cases in fall and winter.
Diseases Caused by Kingella
The most common manifestations of K. kingae disease are
Skeletal infections (septic arthritis, osteomyelitis)
The most common skeletal infection is septic arthritis, which most frequently affects large, weight-bearing joints, especially the knee and ankle. This infection occurs as a result of occult hematogenous spread (1).
Osteomyelitis most frequently involves bones of the lower extremities. Onset is insidious, and diagnosis is often delayed. Hematogenous invasion of intervertebral disks (spondylodiscitis) can occur, most commonly in the lumbar intervertebral spaces.
Kingella endocarditis has been reported in all age groups, but it is rare in adults. Endocarditis may involve native or prosthetic valves. Kingella is a component of the so-called HACEK group (Haemophilus species, Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, Kingella kingae), which includes fastidious gram-negative bacteria capable of causing endocarditis.
Bacteremia without another nidus of infection or endocarditis is common in children but rare in adults.
Rare manifestations include pneumonia, epiglottitis, meningitis, abscesses, and ocular infections.
Diseases caused by Kingella reference
1. Yagupsky P. Kingella kingae: carriage, transmission, and disease. Clin Microbiol Rev. 2015;28(1):54-79. doi:10.1128/CMR.00028-14
Diagnosis of Kingella Infections
Cultures
Diagnosis requires laboratory isolation from blood, fluids, or tissues thought to be infected.
Treatment of Kingella Infections
A penicillin or cephalosporin
Kingella organisms are generally susceptible to most penicillins and cephalosporins. However, antimicrobial susceptibility testing is recommended to guide therapy because rare isolates can produce TEM-1 beta-lactamase (1
Treatment reference
1. Banerjee A, Kaplan JB, Soherwardy A, et al. Characterization of TEM-1 β-Lactamase-Producing Kingella kingae Clinical Isolates. Antimicrob Agents Chemother. 2013;57(9):4300-4306. doi:10.1128/AAC.00318-13
