Haemophilus influenzae type a as a cause of paediatric septic arthritis

Abstract

Introduction:Incidence rates of invasive Haemophilus influenzae serotype b disease have decreased significantly since the introduction of the Hib vaccine; however, the rates in indigenous populations remain disproportionately high, specifically in the paediatric population. Additionally, with the decline of type b invasive infections, there has been a rebound in the incidence of invasive infections caused by other strains of H. influenzae, particularly serotype a.Case presentation:We present a paediatric case of septic arthritis caused by H. influenzae type a in a toddler that was fully resolved following antibiotic therapy. This report adds to other reports of septic arthritis in indigenous populations as shown through a review of recently documented H. influenzae type a septic arthritis cases.Conclusion:Socio-economic risk factors for invasive H. influenzae type a disease, such as poverty, poor housing conditions, overcrowding, smoking and substance abuse during pregnancy, as well as the need for H. influenzae type a immunization of vulnerable populations, are discussed.

Characterization of natural bactericidal antibody against Haemophilus influenzae type a in Canadian First Nations: A Canadian Immunization Research Network (CIRN) Clinical Trials Network (CTN) study

“…These findings suggest that high Hia circulation rates in First Nations communities stimulate the development of antibodies because of an increased exposure of the population to Hia antigens. Indeed, our epidemiological studies have demonstrated that in this region, most cases of invasive Hia disease occur in First Nations [ 12 , 13 , 22 , 24 , 33 ]. Moreover, our ongoing research in First Nations communities of Northwestern Ontario identified Hia as a common cause of pediatric otitis media and found that approximately 8% of 3–5 year old children carry Hia in the nasopharynx (unpublished observations).…”

Report of Haemophilus Influenzae serotype a intracranial infections in older children

“…There are growing numbers of sporadic case reports, case series, and retrospective studies with various clinical presentations of invasive Hia infection globally. [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] Most of these reports show the greatest burden of invasive Hia disease in children ≤ 5 years or adults > 65 years, 32 with short-and long-term adverse outcomes exclusively in young children ≤ 5 years of age. 23,31,33 We described two cases of invasive Hia infection in children > 5 years of age who presented within a 2-month period to our hospital.…”

Invasive Haemophilus influenzae Type F Infection Complicated by Subarachnoid Phlegmon and Cortical Venous Thrombosis

“…H influenzae is strictly a human pathogen, gram-negative coccobacillus, which usually infects the upper respiratory tract and can cause serious invasive infections, especially in children younger than 5 years. [1][2][3][4][5][6][7][8] There are 6 encapsulated serotypes characterized by distinctive capsular polysaccharides (a-f), as well as 3 nonencapsulated or nontypeable strains. 2,3,7 In 1994, invasive Hif was reported to occur at frequency of 1.9 cases per 1 million children with pneumonia and meningitis being the most common presentations.…”

“…2,3,7 In 1994, invasive Hif was reported to occur at frequency of 1.9 cases per 1 million children with pneumonia and meningitis being the most common presentations. 9 The percentage of Hif infections has declined with universal introduction of the conjugate vaccine.10 With this decline, the incidence of invasive infections caused by nontypeable or other strains of H influenzae, 5,7,11 particularly serotype f, has grown in the United States as well as other countries. [12][13][14] In the pediatric population, pneumonia and meningitis are the most common forms of severe Hif infection.…”