Mycoplasma infection and Kawasaki disease

Clarithromycin Plus Intravenous Immunoglobulin Therapy Can Reduce the Relapse Rate of Kawasaki Disease: A Phase 2, Open-Label, Randomized Control Study

Background

We previously reported that biofilms and innate immunity contribute to the pathogenesis of Kawasaki disease. Therefore, we aimed to assess the efficacy of clarithromycin, an antibiofilm agent, in patients with Kawasaki disease.

Methods and Results

We conducted an open‐label, multicenter, randomized, phase 2 trial at 8 hospitals in Japan. Eligible patients included children aged between 4 months and 5 years who were enrolled between days 4 and 8 of illness. Participants were randomly allocated to receive either intravenous immunoglobulin (IVIG) or IVIG plus clarithromycin. The primary end point was the duration of fever after the initiation of IVIG treatment. Eighty‐one eligible patients were randomized. The duration of the fever did not differ between the 2 groups (mean±SD, 34.3±32.4 and 31.1±31.1 hours in the IVIG plus clarithromycin group and the IVIG group, respectively [P=0.66]). The relapse rate of patients in the IVIG plus clarithromycin group was significantly lower than that in the IVIG group (12.5% versus 30.8%, P=0.046). No serious adverse events occurred during the study period. In a post hoc analysis, the patients in the IVIG plus clarithromycin group required significantly shorter mean lengths of hospital stays than those in the IVIG group (8.9 days versus 10.3 days, P=0.049).

Conclusions

Although IVIG plus clarithromycin therapy failed to shorten the duration of fever, it reduced the relapse rate and shortened the duration of hospitalization in patients with Kawasaki disease.

Clinical Trial Registration

URL: http://www.umin.ac.jp/ctr/index.htm. Unique identifier: UMIN000015437.

Incomplete Kawasaki disease in a 12-month-old girl presenting with cardiac murmur and iron deficiency anemia

Kawasaki disease (KD) is an acute necrotizing vasculitis that occurs in children <5 years of age. The cause of KD remains unknown, but various complications, including dilatation of the coronary arteries, can occur. Coronary artery aneurysm or ectasia are the most important complications of KD. Children with suspected KD who do not fulfill the diagnostic criteria may have incomplete KD. Given that incomplete KD is associated with delayed diagnosis and treatment, children with incomplete KD have a high risk of cardiovascular complications. Meanwhile, iron deficiency anemia (IDA) is one of the most prevalent micronutrient deficiencies in the world. Children with IDA are prone to infection and inflammation. We report the case of a 12-month-old girl with incomplete KD who presented with cardiac murmur and severe IDA.

Influenza infection and Kawasaki disease

INTRODUCTION

The objective of this study was to investigate the possible link between influenza (Flu) infection and Kawasaki disease (KD).

METHODS

We examined the medical records of 1,053 KD cases and 4,669 influenza infection cases hospitalized at our institute from January 1, 2011 to December 31, 2013. Cases of KD with concomitant influenza infection formed the KD + Flu group. Each KD + Flu case was matched with 2 KD cases and 2 influenza infection cases, and these cases were assigned to the KD group and Flu group, respectively. The differences in the principal clinical manifestations, course of disease, incomplete KD rate, intravenous immunoglobulin (IVIG) resistance rate, and echocardiographic detection results between the KD + Flu group and KD group were compared. The fever durations and laboratory test results of these three groups were compared.

RESULTS

1) The seasonal variations of the KD + Flu group, KD group and Flu group were similar. 2) The morbidity rate of incomplete KD was higher in the KD + Flu group compared with the KD group. 3) Patients in the KD + Flu group exhibited a longer time to KD diagnosis compared with patients in the KD group. 4) The KD + Flu group exhibited the longest fever duration among the three groups. 5) The CRP and ESR values in the KD + Flu group were higher those in the Flu or KD groups.

CONCLUSIONS

Concomitant influenza infection affects the clinical manifestations of KD and can impact the laboratory test results and the diagnosis and treatment of the disease. However, it remains unclear whether influenza contributes to KD etiology.

Co-morbidity of Kawasaki disease

Despite more than four decades of investigation, the etiology of Kawasaki disease remains obscure, and none of the proposed etiologic theories for the disease have achieved independent confirmation. Clinical and epidemiologic features support an infectious cause, but the etiology remains unclear. The authors present a case of Kawasaki disease associated with Epstein-Barr virus and Mycoplasma pneumoniae infection in a 3.5-y-old boy. He received two doses of intravenous immunoglobulin due to prolonged course of Kawasaki disease but later had complicated autoimmune haemolytic anaemia. His prolonged fever subsided after azithromycin administration. Epstein-Barr virus infection was confirmed by molecular microbiological pathology of cervical lymph node and serological tests. The serological tests for Mycoplasma pneumoniae also revealed a positive result. Thus, it is concluded that Mycoplasma pneumoniae and Epstein-Barr virus infections may occur simultaneously in a child with Kawasaki disease. In addition, autoimmune hemolytic anaemia may be noted in Kawasaki disease patients after high-dose IVIG administration. To the authors' knowledge, this is the first report of Kawasaki disease with Epstein-Barr virus and Mycoplasma pneumoniae in the English-language literature.

Detection of multiple superantigen genes in stools of patients with Kawasaki disease

OBJECTIVES

To investigate whether superantigens (SAgs) are involved in the development of Kawasaki disease (KD) by examining SAg genes in the stool of patients with KD.

STUDY DESIGN

Stool specimens were obtained from 60 patients with KD and 62 age-matched children (36 children with acute illness and 26 healthy children). Total DNA was extracted from these stool samples. Using polymerase chain reaction, we examined genes of 5 SAgs: streptococcal pyrogenic exotoxin-A (SPE-A), SPE-C, SPE-G, SPE-J, and toxic shock syndrome toxin-1.

RESULTS

At least 1 of the 5 SAg genes was detected in 42 (70%) specimens from patients with KD, 14 (38.9%) from the febrile group, and 7 (26.9%) from the healthy group. The detection rate between subjects with and without KD was of at least 1 of the 5 SAg genes (P < .001), and more than 2 SAg genes were significantly different (P = .002).

CONCLUSIONS

SAg may be involved in the development of KD; data suggest that multiple SAgs may trigger KD.

Infection and vasculitis

Vasculitis may be associated with infection, immunization or anti-microbial drugs. Infections are responsible for a number of different types of vasculitis. Conversely, patients with vasculitis may develop infections, which sometimes mimic relapse. The aim of this review is to summarize the various aspects of the inter-relationship between vasculitis and infection, and the physiopathological mechanisms involved, in light of our current knowledge from animal models. Currently, a causal relationship between infection and vasculitis has only been established in a few instances and many mechanisms remain hypothetical. This inter-relationship is further assessed from the point of view of clinical presentation and therapeutic options, based on case reports and prospective observational data.

Chapter 11 Kawasaki Disease

Kawasaki disease (KD) is an acute febrile systemic vasculitis usually occurring in children younger than five years, and rarely reported in neonates and adults. This chapter discusses the epidemiology, etiology, pathogenesis, clinical manifestations, and treatments of KD. The etiology still remains unknown, although epidemiological and clinical features strongly suggest an infectious cause. Immunological abnormalities in the acute phase of the disease reflect activation of immune system and marked production of cytokines by activated cells. KD has some similarities to toxin-mediated diseases, both from a clinical and an immunological point of view. The role of one or more superantigens competent of stimulating large numbers of T cells produced by certain strains of Staphylococcus or Streptococcus is discussed in the chapter, in the context of the etiology of KD. Atypical cases are those with fever, acute surgical symptoms, or neurological manifestations as presenting signs. Medical history, physical examination, and laboratory tests including elevated white-blood cell (WBC) count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and low hemoglobin, sodium and albumin levels may help to rule out illnesses mimicking KD. Oral or pulsed corticosteroids in children refractory to intravenous immunoglobulins (IVIG) are an alternative and safe treatment.

Kawasaki disease: what is the epidemiology telling us about the etiology?

Kawasaki disease (KD) is an important and common inflammatory vasculitis of early childhood with a striking predilection for the coronary arteries. It is the predominant cause of paediatric acquired heart disease in developed countries. Despite 40 years of research, the aetiology of KD remains unknown and consequently there is no diagnostic test and treatment is non-specific and sub-optimal. The consensus is that KD is due to one or more widely distributed infectious agent(s), which evoke an abnormal immunological response in genetically susceptible individuals. The epidemiology of KD has been extensively investigated in many populations and provides much of the supporting evidence for the consensus regarding etiology. These epidemiological data are reviewed here, in the context of the etiopathogenesis. It is suggested that these data provide additional clues regarding the cause of KD and may account for some of the continuing controversies in the field.

Elevated serum alanine aminotransferase (ALT) levels in patients with serologically verified Mycoplasma pneumoniae pneumonia

The possibility of liver involvement in Mycoplasma pneumoniae pneumonia is still controversial. This study investigated 33 adult patients with serologically confirmed M. pneumoniae community-acquired pneumonia (CAP) (median age 31 years) and 38 patients with bacteraemic Streptococcus pneumoniae CAP (median age 54 years), all without pre-existing liver disease. Serum alanine aminotransferase (ALT) levels were elevated in 12 (36.4%) patients with M. pneumoniae CAP (median 53.5 U/L), and in four (10.5%) patients with S. pneumoniae CAP (median 61 U/L) (p 0.025). In most patients with M. pneumoniae CAP, the elevated ALT levels decreased during macrolide therapy, although this decrease was not significant.

Two cases of lymphadenopathy with liver dysfunction due to Mycoplasma pneumoniae infection with mycoplasmal bacteraemia without pneumonia

We present two cases of unusual manifestations of Mycoplasma pneumoniae infection: lymphadenopathy with liver dysfunction without pneumonia. One was diagnosed as an infectious mononucleosis-like syndrome and the other as Kawasaki disease. Polymerase chain reaction successfully detected Mycoplasma pneumoniae DNA using blood samples. Mycoplasma pneumoniae can be included in the panel of aetiological agents in patients with lymphadenitis and hepatitis even in the absence of pneumonia.