Lack of association between Kawasaki syndrome and Chlamydia pneumoniae infection: an investigation of a Kawasaki syndrome cluster in San Diego County

An Intriguing Case of Multisystem Inflammatory Syndrome in an Adult Patient with Remote Infection with COVID-19 and Acute Chlamydia

Introduction

COVID-19 is associated with a broad range of immune inflammatory phenomena, with different manifestations in adults and children. We describe a case of COVID-19-related multisystem inflammatory syndrome in an adult (MIS-A), similar to that described in children (MIS-C), which may have been set off by an unrelated secondary infection.

Case

A 27-year-old male patient presented with acute epididymitis secondary to acute Chlamydia infection that progressed to multisystem inflammatory failure with respiratory failure requiring endotracheal intubation and mechanical ventilation, cardiogenic shock with heart failure, and gastrointestinal and renal dysfunction. He tested negative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by reverse transcriptase-polymerase chain reaction on a nasopharyngeal swab thrice within 4 days of presentation, but positive for SARS-CoV-2 immunoglobulin G antibody signifying remote infection. The patient was treated with tocilizumab and steroids, along with doxycycline for concurrent Chlamydia infection, resulting in dramatic improvement in all organ function. We suspect that C. trachomatis infection in this instance may have triggered an aberrant immune response that was shaped by prior exposure to SARS-CoV-2.

Conclusion

We present a case of an adult patient with acute Chlamydia trachomatis infection occurring in the wake of asymptomatic (or at least unrecognized) COVID-19 resulting in MIS-A. Clinicians should be alert to the possibility of other such unusual reactions occurring in the aftermath of COVID-19. This case also highlights the importance for clinicians who care for adult patients of being familiar with the multisystem inflammatory syndrome of children, as an identical syndrome may occur in adult patients.

Viral infections associated with Kawasaki disease

BACKGROUND/PURPOSE

Kawasaki disease (KD) is a disease of unknown cause. To investigate the infectious etiology of Kawasaki disease, we initiated a prospective case-control study to investigate possible links between common viral infections and Kawasaki disease.

METHODS

We enrolled 226 children with KD and 226 age- and sex-matched healthy children from February 2004 to March 2010. Throat and nasopharyngeal swabs were taken for both viral isolation and polymerase chain reaction (PCR) for various viruses.

RESULTS

The mean age of the 226 KD cases was 2.07 years, and the male to female ratio was 1.43 (133 boys to 93 girls). Their mean fever duration was 7.5 days with a mean peak temperature of 39.7°C. In addition to the typical symptoms of fever, neck lymphadenopathy, lip fissure and/or strawberry tongue, skin rash, nonpurulent bulbar conjunctivitis, palm/sole erythema, and induration followed by periungual desquamation, these KD cases also exhibited cough (69%), rhinorrhea (58%), and diarrhea (45%). Cases of KD had a significantly higher positive rate of viral isolation in comparison with the control group (7.5% vs. 2.2%, p = 0.02). Compared with the control group, cases of KD were more likely to have overall positive rates of viral PCR (50.4% vs. 16.4%, p < 0.001) and for various viruses including enterovirus (16.8% vs. 4.4%, p < 0.001), adenovirus (8.0% vs. 1.8%, p = 0.007), human rhinovirus (26.5% vs. 9.7%, p < 0.001), and coronavirus (7.1% vs. 0.9%, p = 0.003).

CONCLUSION

We found that some common respiratory viruses, such as adenoviruses, enteroviruses, rhinoviruses, and coronaviruses, were associated with KD cases.

Effectiveness of pandemic influenza A/H1N1 vaccine for prevention of otitis media in children

Our aim was to evaluate effectiveness of pandemic influenza A/H1N1 vaccine in preventing acute otitis media (AOM) and/or otitis media with effusion (OME), in a randomized, prospective and single-blind study conducted in the children aged of 6-60 months. This study was done between December 1, 2009 and April 30, 2010 during the pandemia between June 2009 and May 2010. On the healthy children, vaccinated against pandemic influenza A/H1N1 and age-matched unvaccinated controls, the rate of AOM, OME, and any otitis media (OM) attack (sum of AOM and OME attacks) confirmed by otoscopic and tympanometric examination, and their associations with risk factors were looked for. Otoscopic and tympanometric evaluation was done twice within the follow-up period of 4-8 weeks. Totally 46 vaccinated and 46 unvaccinated healthy children were enrolled. No difference in rates of AOM, OME, or OM was found between vaccinated and unvaccinated children. But logistic regression analysis revealed that unvaccinated children had 2.9-folds more risk for OME and OM, but not for AOM. Further, male gender and bottle feeding and/or using pacifier revealed significant relationships with AOM.

CONCLUSION

We conclude that pandemic influenza A/H1N1 vaccine prevented OME rather than AOM attacks in children with 6-60 months of age.

Viral upper respiratory tract infection and otitis media complication in young children

BACKGROUND

The common cold or upper respiratory infection (URI) is highly prevalent among young children and often results in otitis media (OM). The incidence and characteristics of OM complicating URI due to specific viruses have not been well studied.

METHODS

We performed a prospective, longitudinal cohort study of 294 healthy children (age range, 6 months to 3 years). Each child was observed for 1 year to assess the occurrence of URI, acute OM (AOM), and OM with effusion (OME) complicating URI due to specific viruses.

RESULTS

We documented 1295 URI episodes (5.06 episodes per child-year) and 440 AOM episodes (1.72 episodes per child-year). Virus studies were performed for 864 URI episodes; 63% were virus positive. Rhinovirus and adenovirus were most frequently detected during URI. The overall incidence of OM that complicated URI was 61%, including a 37% incidence of AOM and a 24% incidence of OME. Young age was the most important predictor of AOM that complicated URI. AOM occurred in approximately one-half of children with URI due to adenovirus, respiratory syncytial virus, or coronavirus and in approximately one-third of those with URI due to influenza virus, parainfluenza virus, enterovirus, or rhinovirus.

CONCLUSIONS

More than 60% of episodes of symptomatic URI among young children were complicated by AOM and/or OME. Young age and specific virus types were predictors of URI complicated by AOM. For young children, the strategy to prevent OM should involve prevention of viral URI. The strategy may be more effective if the priority is given to development of means to prevent URI associated with adenovirus and respiratory syncytial virus.

Chinchilla and murine models of upper respiratory tract infections with respiratory syncytial virus

Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in infants and the elderly. While the primary infection is the most serious, reinfection of the upper airway throughout life is the rule. Although relatively little is known about either RSV infection of the upper respiratory tract or host mucosal immunity to RSV, recent literature suggests that RSV is the predominant viral pathogen predisposing to bacterial otitis media (OM). Herein, we describe mouse and chinchilla models of RSV infection of the nasopharynx and Eustachian tube. Both rodent hosts were susceptible to RSV infection of the upper airway following intranasal challenge; however, the chinchilla proved to be more permissive than the mouse. The chinchilla model will likely be extremely useful to test the role of RSV in bacterial OM and the efficacy of RSV vaccine candidates designed to provide mucosal and cytotoxic T-lymphocyte immunity. Ultimately, we hope to investigate the relative ability of these candidates to potentially protect against viral predisposal to bacterial OM.

Epidemiologic features of Kawasaki disease in Taiwan, 1996-2002

OBJECTIVE

Kawasaki disease (KD) is the most common acquired heart disease in children worldwide. The incidence of KD varies among different countries, with Asian countries supposedly having higher incidences than Western countries. However, the incidence of KD in Taiwan has not been well investigated.

METHODS

Since the implementation of Taiwan's National Health Insurance (NHI) in 1995, NHI has covered health care for >96% its population. Using the NHI database from 1996 to 2002, we investigated epidemiologic features of KD (International Classification of Diseases, Ninth Revision, code 446.1), the rate of coronary artery aneurysm formation (International Classification of Diseases, Ninth Revision, code 414.11), and the change in incidence during the recent 7 years. We also compared the annual incidences in Taiwan with those reported by other countries.

RESULTS

During the 7-year study period, KD occurred most frequently in the summer and least frequently in winter. It is interesting that the highest peak occurred in the summer of 1998 at the same time that Taiwan's enterovirus 71 epidemic was occurring. Ninety-one percent of KD cases occurred in children who were <5 years old, and the male-to-female ratio was 1.70:1. Recurrence of KD was found in 1.3% (94 of 7305) of these children, and coronary artery aneurysm was found in 7.3% (536 of 7305). The annual incidence per 100,000 children was 146 in children <1 year old, 98 in 1-year-old children, 51 in 2-year-old children, 28 in 3-year-old children, 19 in 4-year-old children, and 5.3 in 5- to 9-year-old children; the incidence of KD decreased with increased age. The overall incidence was 66 cases per 100,000 children <5 years old from 1996 to 2002 with the annual incidence not differing significantly during the 7-year study period.

CONCLUSIONS

KD in Taiwan occurs more frequently in boys and in the summer months. During the 7-year study period, the annual KD incidence in Taiwan of 66/100000 in children <5 years old was the second highest in the world after Japan.

Elevated levels of matrix metalloproteinase 9 and tissue inhibitor of metalloproteinase 1 during the acute phase of Kawasaki disease

Kawasaki disease (KD) is an acute, self-limiting, multisystem vasculitis of unknown etiology affecting infants and young children. Unless treated promptly with high-dose intravenous gamma globulin and aspirin, patients frequently develop coronary aneurysms. Previously, matrix metalloproteinase 9 (MMP-9), which is secreted complexed to tissue inhibitor of metalloproteinase 1 (TIMP-1), has been implicated in abdominal aortic aneurysm formation. Since the clinical and pathological features of KD include inflammation and weakening of blood vessels, we analyzed acute- and convalescent-phase paired plasma or serum samples from 31 KD patients, 7 patients who did not completely meet the criteria for KD, and 26 non-KD controls (9 febrile and 17 afebrile patients) for pro-MMP-9 (92 kDa) enzyme activity by gelatin zymography and for active MMP-9 (83 kDa), pro-MMP-9, and TIMP-1 protein levels by enzyme-linked immunosorbent assay. Statistical analysis was performed by using Student t tests, linear regression, and the Wilcoxon rank-sum test. Markedly elevated pro-MMP-9 enzymatic activity, pro-MMP-9 protein levels, and TIMP-1 protein levels were found during the acute phase of illness in patients with clinically established KD and in patients who were suspected of having KD but did not meet all of the criteria. There was no significant difference in active MMP-9 levels. Furthermore, pro-MMP-9 and TIMP-1 protein levels were significantly elevated among KD patients, compared to those of febrile and afebrile non-KD controls. The significantly elevated pro-MMP-9 enzyme and protein levels during the acute phase of KD may reflect vascular remodeling or an inflammatory response to a microbial agent, suggesting a pathophysiological role for MMP-9 in coronary aneurysm formation.

Incidence of Henoch-Schönlein purpura, Kawasaki disease, and rare vasculitides in children of different ethnic origins

BACKGROUND

The frequency and ethnic variation of Henoch-Schönlein purpura, Kawasaki disease, and rarer vasculitides during childhood are not well characterised. Our aim was to ascertain the incidence and ethnic distribution of these conditions in children resident in a region of the UK with a diverse ethnic mix.

METHODS

1.1 million children younger than age 17 years live in the West Midlands. Between Sept 1, 1996, and Aug 31, 1999, we surveyed this population with monthly questionnaires sent to 321 consultants, a single questionnaire sent to 2860 family doctors, and review of 406 case notes with diagnostic codes for vasculitis. We included in the analyses children who fulfilled established criteria for vasculitis with disease onset during the study, and calculated incidence rates from population rates derived from the census of 1991.

FINDINGS

We identified 586 new instances of vasculitis and connective tissue disease. The estimated annual incidence of Henoch-Schönlein purpura was 20.4 per 100000, and was highest between the ages of 4 years and 6 years (70.3 per 100000). The estimated annual incidence of Kawasaki disease was 5.5 per 100000 in children younger than 5 years, and was highest in Indian subcontinent Asian children (14.6 per 100000). Indian subcontinent Asian and black children had the highest incidence of systemic lupus erythematosus, juvenile dermatomyositis, and other primary systemic vasculitides.

INTERPRETATION

Childhood Henoch-Schönlein purpura is more frequent in the West Midlands than previously reported, and Kawasaki disease has a higher incidence than previously indicated in the UK, with the highest incidence in Indian subcontinental Asian children. Other vasculitis is rare in childhood.

Development and evaluation of real-time PCR-based fluorescence assays for detection of Chlamydia pneumoniae

Chlamydia pneumoniae is an important respiratory pathogen recently associated with atherosclerosis and several other chronic diseases. Detection of C. pneumoniae is inconsistent, and standardized PCR assays are needed. Two real-time PCR assays specific for C. pneumoniae were developed by using the fluorescent dye-labeled TaqMan probe-based system. Oligonucleotide primers and probes were designed to target two variable domains of the ompA gene, VD2 and VD4. The limit of detection for each of the two PCR assays was 0.001 inclusion-forming unit. Thirty-nine C. pneumoniae isolates obtained from widely distributed geographical areas were amplified by the VD2 and VD4 assays, producing the expected 108- and 125-bp amplification products, respectively. None of the C. trachomatis serovars, C. psittaci strains, other organisms, or human DNAs tested were amplified. The amplification results of the newly developed assays were compared to the results of culturing and two nested PCR assays, targeting the 16S rRNA and ompA genes. The assays were compared by testing C. pneumoniae purified elementary bodies, animal tissues, 228 peripheral blood mononuclear cell (PBMC) specimens, and 179 oropharyngeal (OP) swab specimens obtained from ischemic stroke patients or matched controls. The real-time VD4 assay and one nested PCR each detected C. pneumoniae in a single, but different, PBMC specimen. Eleven of 179 OP specimens (6.1%) showed evidence of the presence of C. pneumoniae in one or more tests. The real-time VD4 assay detected the most positive results of the five assays. We believe that this real-time PCR assay offers advantages over nested PCR assays and may improve the detection of C. pneumoniae in clinical specimens.

Recent developments in Kawasaki disease

Kawasaki disease is now being recognized as the leading cause of acquired heart disease in children in North America and Japan. This review discusses the recent developments and controversies in Kawasaki disease. Increasing evidence has supported an infectious etiology for Kawasaki disease; however, the debate continues as to whether the inflammatory response results from a conventional antigen or a superantigen. Recent immunohistochemistry findings suggest many vascular growth factors then play a role in the formation of the coronary artery lesions. Many studies have focused on the identification and therapy for patients resistant to conventional therapy, as well as the long-term prognosis of Kawasaki disease survivors. The recent advances in Kawasaki disease are helping to provide some clues in the etiology, pathogenesis and therapy for Kawasaki disease.

Failure to demonstrate Chlamydia pneumoniae in cardiovascular tissue from children with Kawasaki disease

Chlamydia pneumoniae has been associated with atherosclerosis and myocardial infarction in adults. Coronary artery tissues of five fatal cases of Kawasaki disease were examined by PCR; none was positive.

Relationship of climate, ethnicity and socioeconomic status to Kawasaki disease in San Diego County, 1994 through 1998

BACKGROUND

Kawasaki disease (KD) is the most common cause of acquired heart disease in children in the United States. By monitoring trends in patient numbers and demographics during a 5-year period, we were able to explore the relationship between climate, ethnicity, socioeconomic status and susceptibility to KD.

METHODS

We conducted active surveillance for all patients hospitalized with KD in San Diego County from 1994 through 1998. Data on seasonal variation in monthly rainfall and temperature were obtained from the US Meteorological Service. Patient sex, age, date of admission and self-reported ethnicity were identified from patient medical records. Socioeconomic status was assessed on the basis of insurance status among patients hospitalized at a single institution.

RESULTS

During the 5-year period there were 169 cases of KD in San Diego County. The overall annual incidence of KD in children < 5 years of age ranged from 8.0 to 15.4/100 000. KD incidence was inversely associated with average monthly temperature (r = -0.47, P < 0.001) and positively associated with average monthly precipitation (r = -0.52, P < 0.001). Asian/Pacific Islanders < 5 years of age were 2.7 times as likely and Hispanics were one-third as likely to be hospitalized for KD than children from all other ethnic groups combined. Children with private or military insurance in all ethnic groups were more likely to have a diagnosis of KD than children with government assistance or no insurance. After controlling for insurance status, only Asian/Pacific Islanders remained at increased risk (rate ratio, 2.14) for KD relative to all other ethnic groups combined.

CONCLUSION

KD is a common childhood vasculitis of unknown etiology. The skewed ethnic distribution and seasonality are consistent with the hypothesis that KD is an infectious disease that is influenced by environmental and genetic factors.