Isolation of Kingella kingae from a corneal ulcer

Leptotrichia species isolated from a chronic recurrent corneal ulcer

Purpose

To report a case of recurrent corneal ulcer caused by an oropharyngeal cavity pathogen.

Observations

A patient presented with recurrent corneal ulcers with hypopyon. Leptotrichia species was eventually isolated from the corneal ulcer on bacterial polymerase chain reaction (PCR) after many negative bacterial culture attempts. Due to correct identification of the pathogen, it was discovered that the patient was exposing her eye to saliva. Modification of patient behavior and initiation of the appropriate antibacterial treatment resulted in resolution of recurrent episodes of active infection.

Conclusions

Although Leptotrichia species are not typically ocular pathogens, they can become pathogenic in the cornea with direct transmission from the oral cavity to the eye.

Kingella kingae Keratitis in a Child with Underlying Vernal Keratoconjunctivitis

Kingella kingae had rarely been reported as a causative organism for corneal ulcer and had not been described before in vernal keratoconjunctivitis (VKC). Generally regarded as commensals of respiratory tract particularly in young children, it had however been isolated from the corneal ulcer scraping of both adult and children. We report a case of bacterial ulcer with isolation of Kingella kingae from the corneal scraping in a young child with underlying VKC.

Kingella kingae: carriage, transmission, and disease

Kingella kingae is a common etiology of pediatric bacteremia and the leading agent of osteomyelitis and septic arthritis in children aged 6 to 36 months. This Gram-negative bacterium is carried asymptomatically in the oropharynx and disseminates by close interpersonal contact. The colonized epithelium is the source of bloodstream invasion and dissemination to distant sites, and certain clones show significant association with bacteremia, osteoarthritis, or endocarditis. Kingella kingae produces an RTX (repeat-in-toxin) toxin with broad-spectrum cytotoxicity that probably facilitates mucosal colonization and persistence of the organism in the bloodstream and deep body tissues. With the exception of patients with endocardial involvement, children with K. kingae diseases often show only mild symptoms and signs, necessitating clinical acumen. The isolation of K. kingae on routine solid media is suboptimal, and detection of the bacterium is significantly improved by inoculating exudates into blood culture bottles and the use of PCR-based assays. The organism is generally susceptible to antibiotics that are administered to young patients with joint and bone infections. β-Lactamase production is clonal, and the local prevalence of β-lactamase-producing strains is variable. If adequately and promptly treated, invasive K. kingae infections with no endocardial involvement usually run a benign clinical course.

Kingella kingae keratitis

We present the first two cases of Kingella kingae keratitis in adults. This species is a rare isolate from ophthalmic samples for which final identification was obtained with matrix-assisted laser desorption ionization-time of flight mass spectrometry. One of the patients recovered uneventfully with topical therapy. Results from the second patient cannot be confirmed as he was lost to follow-up.

Isolation of Kingella denitrificans from a corneal ulcer

PURPOSE

To report a case of a corneal ulcer caused by an unusual pathogen.

DESIGN

Case report.

METHODS

Clinical review describing initial presentation, course, and outcome of 1 patient with a corneal ulcer caused by Kingella denitrificans.

RESULTS

A 77-year-old man with a prior history of 4 penetrating keratoplasties in the right eye for herpes simplex virus keratitis presented with a 3-day history of a red painful right eye. On examination, he was found to have a corneal ulcer identified by culture as K. denitrificans.

CONCLUSIONS

Although Kingella spp. is not a common ocular pathogen, it can infect the cornea, especially when the host immune defense is altered.

Kingella kingae: from medical rarity to an emerging paediatric pathogen

In recent years, Kingella kingae has emerged as an important cause of invasive infections in young children, especially septic arthritis, osteomyelitis, spondylodiscitis, bacteraemia, and endocarditis, and less frequently lower respiratory tract infections and meningitis. The organism is part of the pharyngeal flora of young children and is transmitted from child-to-child. The clinical presentation of invasive K kingae disease is often subtle and laboratory tests are frequently normal. A substantial fraction of children with invasive K kingae infections have a recent history of stomatitis or symptoms of upper-respiratory-tract infection. The organism is susceptible to a wide array of antibiotics that are usually given empirically to young children including beta lactams, and with the exception of cases of endocarditis, the disease runs a benign clinical course. Although isolation and recognition of the organism is not difficult, clinicians and microbiologists should be aware of its fastidious nature. To optimise the recovery of K kingae, inoculation of synovial fluid specimens into blood culture vials is strongly recommended.

Kingella kingae infections in children

OBJECTIVE

To increase awareness of Kingella kingae infections in children by presenting four cases seen at the Gold Coast Hospital, Southport, Queensland, and reviewing the literature.

METHODOLOGY

Records of the four cases were reviewed and relevant information described. A MEDLINE search of the English literature from 1983 to 1998 was conducted.

RESULTS

Osteoarticular infections are the commonest type of invasive paediatric infection but bacteraemia and endocarditis also occur. Isolation of the organism is difficult but inoculation of the specimen into enriched blood culture systems improves the recovery rate. The majority of isolates are sensitive to beta-lactam antibiotics but resistance has been described.

CONCLUSIONS

Kingella kingae infections in children are more common than previously recognized. The organism should be actively sought in any child with suspected osteoarticular infections. Recommended empiric therapy is a third generation cephalosporin until susceptibility to penicillin is confirmed.

[Multifocal invasive Kingella kingae infection]

CASE REPORT

A 2-year-old child, non immunodeficient, presented with septicemia due to Kingella kingae successively complicated by meningitis, arthritis of one knee and endocarditis. Outcome was favourable after a long and adjusted antibiotherapy, involving in particular for the endocarditis ceftriaxone (100 mg/kg/d) and amikacin (20 mg/kg/d) during 3 weeks, then amoxicillin per os (200 mg/kg/d) during 3 weeks.

CONCLUSIONS

Bacteriologic characteristics of the bacteria, the culture of which requires medium base with additional nutrient are reviewed. The tropism of Kingella kingae is essentially osteoarticular and cardiac as shown by the cases reported in the literature. Its susceptibility to antibiotics explains the frequent favourable outcome.