Mycoplasma pneumoniae infection–induced erythema nodosum, anaphylactoid purpura, and acute urticaria in 3 people in a single family

Mycoplasma infection aggravates cardiac involvements in Kawasaki diseases: a retrospective study

Background

Mycoplasma pneumoniae (MP) infection serves as a substantial cofactor in Kawasaki disease (KD) among patients. Although the dominant issue triggering KD has recently focused on MP infection, the complete demonstration of the relationship between MP infection and KD remains elusive. This study endeavors to scrutinize and compare the clinical manifestations and cardiac involvement between MP-triggered KD and non-infection-associated KD.

Method

This retrospective study (2023-039, approved by the Institutional Review Board of West China Second University Hospital of Sichuan University) encompassed 247 consecutive patients diagnosed with KD between June 2017 and December 2022. Patients were categorized into two groups: the MP group (n = 38) and the non-MP group (n = 209). Univariable analysis was utilized to discern differences in clinical features, severity of inflammation, and initial or persistent cardiac complications between the two groups.

Results

The MP group exhibited a more intricate clinical profile compared with the non-MP group, characterized by prolonged hospital stays, a higher incidence of incomplete KD, and elevated comorbidities. In addition, MP infection correlated with severe hematological disorders, coagulation dysfunction, and myocardial injuries. Our findings revealed that MP infection led to prolonged inflammation after initial treatment with intravenous immunoglobulin. Although initial cardiac assessments failed to discern disparities between the two groups, MP infection notably exacerbated coronary artery aneurysms (CAAs), resulting in sustained dilation.

Conclusions

Recognizing MP infection as a significant infectious factor associated with KD is imperative. In patients with KD, MP infection significantly prolongs inflammation and causes hematological disturbances during the initial treatment phase. Moreover, the presence of MP infection exacerbates the progression of CAAs and myocardial injuries during the subacute phase of KD, consequently contributing to the persistence of CAAs.

Chronic Spontaneous and Inducible Urticaria Associated With Mycoplasma pneumoniae Infection

Acute childhood urticaria is a common disorder that has been associated with infections. In a few children, it may last for more than six weeks, thereafter it is characterized as chronic urticaria (CU). We report two cases, one suffering from chronic spontaneous urticaria and one chronic inducible urticarias (dermographism and cold urticaria). Both children had concomitant respiratory symptoms that were associated with Mycoplasma pneumoniae (MP) infection. Urticarias' symptoms and signs were refractory to regular antihistamines dose but showed marked improvement or complete resolution following clarithromycin administration. CU response to antibiotics pointed strongly to a potential causative role of MP in the pathogenesis of chronic spontaneous and chronic inducible urticarias. It is not clear if MP was the etiopathogenic cause or just the trigger. Nevertheless, refractory to antihistamines urticarias associated with MP infection may respond to antibiotics, which should be considered as an alternative therapeutic approach.

Atypical Bacterial Pathogens and Small-Vessel Leukocytoclastic Vasculitis of the Skin in Children: Systematic Literature Review

Leukocytoclastic small-vessel vasculitis of the skin (with or without systemic involvement) is often preceded by infections such as common cold, tonsillopharyngitis, or otitis media. Our purpose was to document pediatric (≤18 years) cases preceded by a symptomatic disease caused by an atypical bacterial pathogen. We performed a literature search following the Preferred Reporting of Systematic Reviews and Meta-Analyses guidelines. We retained 19 reports including 22 cases (13 females and 9 males, 1.0 to 17, median 6.3 years of age) associated with a Mycoplasma pneumoniae infection. We did not find any case linked to Chlamydophila pneumoniae, Chlamydophila psittaci, Coxiella burnetii, Francisella tularensis, or Legionella pneumophila. Patients with a systemic vasculitis (N = 14) and with a skin-limited (N = 8) vasculitis did not significantly differ with respect to gender and age. The time to recovery was ≤12 weeks in all patients with this information. In conclusion, a cutaneous small-vessel vasculitis with or without systemic involvement may occur in childhood after an infection caused by the atypical bacterial pathogen Mycoplasma pneumoniae. The clinical picture and the course of cases preceded by recognized triggers and by this atypical pathogen are indistinguishable.

Clinical characteristics of Kawasaki disease and concurrent pathogens during isolation in COVID-19 pandemic

BACKGROUND

The aim of this study is to explore the characteristics of Kawasaki disease (KD) and concurrent pathogens due to a stay-at-home isolation policy during coronavirus disease 2019 (COVID-19) epidemic.

METHODS

All patients with KD admitted between February and April in 2015-2020, were classified into before (group 1, in 2015-2019) and after (group 2, in 2020) isolation groups. A total of 4742 patients [with KD (n = 98) and non-KD (n = 4644)] referred to Mycoplasma pneumoniae (MP) and virus detection were analyzed in 2020. Clinical characteristics, laboratory data, and 13 pathogens were analyzed retrospectively.

RESULTS

Group 2 had a significantly increased incidence of KD (0.11%) with 107 patients compared to that of group 1 (0.03%) with 493 patients. The comparisons of oral mucosal change, strawberry tongue, desquamation of the fingertips, cervical lymphadenopathy and neutrophil percentage decreased in group 2 compared to group 1. The infection rate of MP increased significantly in group 2 (34.7%) compared to group 1 (19.3%), while the positive rate of viruses decreased significantly in group 2 (5.3%) compared to group 1 (14.3%). In 2020, the positive rate of MP infection increased significantly in patients with KD compared to the increase in patients with non-KD. The infection rate of MP for younger children aged less than 3 years old was higher in group 2 than in group 1.

CONCLUSION

Compared with the characteristics of KD from 2015 to 2019 years, the incidence of KD was increased in 2020 and was accompanied by a high incidence of MP infection, especially in younger children (less than 3 years old) during the isolation due to COVID-19 pandemic.

Impact of mycoplasma pneumonia infection on urticaria: A nationwide, population-based retrospective cohort study in Taiwan

Mycoplasma pneumonia (MP) infection might be pathogenically closely related to urticaria. This study is a nationwide population-based cohort study from 1997 to 2013, which investigated the association between MP infection and urticaria in Taiwan. A total of 1,175 patients were included for the study group, and 2,350 for the control group. Multivariate Cox regression analysis was performed to estimate the adjusted hazard ratio (aHR) for urticaria. Result showed that 254 patients with new-onset urticaria were involved in the study group and 465 incident cases in the control group. The incidence rates (per 100,000 person-months) of urticaria were 37.2 and 32.5 in the study and control groups, respectively. The relative risk is 1.1 (95% CI = 1.0–1.3) indicating no significant correlation between MP and urticaria. The multivariate analysis revealed that the risk of urticaria with MP infection (aHR = 1.1, P = 0.1058) had no statistically significance difference compared to the control group. However, the risk of urticaria in MP-infected patients aged between 20 and 59 years old was found to have increased (aHR = 1.6, 95% CI = 1.1–2.2) prior to a diagnosis.

The role of mixed Mycoplasma and Herpesvirus infections in case of skin lesions in children

Numerous literature data show the role of mycoplasma infection in the development of non-respiratory lesions of various organs and systems, including the skin. Herpesvirus and mycoplasma infections can trigger the development of immune-mediated inflammatory reactions of the skin and mucous membranes — erythema multiforme exudative, Stevens-Johnson syndrome, vesicular pustular dermatosis — Sneddon-Wilkinson syndrome, etc.

In order to study the frequency and nature of skin lesions with mycoplasmosis combined with herpesvirus infection, 45 patients aged 3 to 15 years of life were observed. A comprehensive clinical and laboratory study revealed skin lesions in 27 patients associated with current mycoplasma and herpesvirus infections. Thus, multiforme exudative erythema in the small form variant was diagnosed in 13 patients, skin vasculitis in 4, hemorrhagic purpura in 3, urticaria rash in 3, erythema nodosum in 2, mucositis in 2 children. In 18 children, a combined mycoplasma and herpesvirus infection was established. In 9 children, a mono infection was detected (in 5 — herpes virus and in 4 — mycoplasma).

All observed patients showed antibodies to smooth muscle antigens in titers from 1:80 to 1:160 (normal 1:40) and in the vast majority (in 24 patients) — antibodies to vascular endothelial antigens in titers from 1:80 to 1:320 (with the norm of 1:40). Compaction of the intima-media complex was detected in 6 patients with monoinfection and in 16 patients with co-infection, according to ultrasound duplex scanning of the vessels of the brachiocephalic department.

Thus, for various immuno-inflammatory, allergic skin diseases, screening for infections, in particular, mycoplasma and herpesvirus, is necessary to optimize treatment.

Pediatric Lip Adhesion Following Bullous Erythema Multiforme and Review of Similar Oral Complications

Background:

Erythema multiforme (EM) is a mucocutaneous disease most often associated with preceding herpes simplex virus or Mycoplasma pneumoniae infection. It is characterized by targetoid lesions occurring on the limbs and head and neck. Mucosal involvement can be extensive.

Objective:

We report a case of lip adhesion as a complication of EM in a child who required corrective surgery and review similar oral commissure complications.

Methods:

We completed a review of the literature for similar cases using PubMed and Medline.

Conclusions and Relevance:

We present the youngest report of lip adhesion due to striking mucositis related to EM. Sequelae of erythema multiforme can be significant, in our case requiring surgery. Meticulous oral hygiene should be encouraged when mucosal lesions are identified.

Examination of the Microbial Spectrum in the Etiology of Erythema Nodosum: A Retrospective Descriptive Study

Even though infections are the most common cause of erythema nodosum (EN), only certain microorganisms take the great interest such as streptococci in knowledge. Our aim was to examine the frequency and type of infections in EN, to determine the characteristics of patients with an infectious etiology, and to discuss the role of these microbes in EN pathology in the context of their interactions with humans. Charts of 81 patients with EN who were seen between 2003 and 2017 were retrospectively reviewed. Identified etiological factors were classified into three groups: infectious, noninfectious, and idiopathic. While there were no significant demographic and clinical differences between the infectious and idiopathic groups, systemic symptoms (p = 0.034) and the number of EN lesions (p = 0.016) were significantly lower; the mean erythrocyte sedimentation rate was significantly higher (p = 0.049), but the mean aspartate aminotransferase value was significantly lower in the infectious group compared to the noninfectious group (p = 0.019). Besides streptococci, many other microbes, including the ones living on and inside us, were identified in the etiology of EN. There is a need for large-scale prospective studies involving control groups for a better understanding of the microbial immunopathology of EN.

Classification of Extrapulmonary Manifestations Due to Mycoplasma pneumoniae Infection on the Basis of Possible Pathogenesis

The list of extrapulmonary manifestations due to Mycoplasma pneumoniae infection can be classified according to the following three possible mechanisms derived from the established biological activity of M. pneumoniae; (1) a direct type in which the bacterium is present at the site of inflammation and local inflammatory cytokines induced by the bacterium play an important role (2) an indirect type in which the bacterium is not present at the site of inflammation and immune modulations, such as autoimmunity or formation of immune complexes, play an important role, and (3) a vascular occlusion type in which obstruction of blood flow induced either directly or indirectly by the bacterium plays an important role. Recent studies concerning extrapulmonary manifestations have prompted the author to upgrade the list, including cardiac and aortic thrombi as cardiovascular manifestations; erythema nodosum, cutaneous leukocytoclastic vasculitis, and subcorneal pustular dermatosis as dermatological manifestations; acute cerebellar ataxia, opsoclonus-myoclonus syndrome, and thalamic necrosis as neurological manifestations; pulmonary embolism as a respiratory system manifestation; and renal artery embolism as a urogenital tract manifestation. Continuing nosological confusion on M. pneumoniae–induced mucositis (without skin lesions), which may be called M. pneumoniae-associated mucositis or M. pneumoniae-induced rash and mucositis separately from Stevens-Johnson syndrome, is argued in the dermatological manifestations. Serological methods are recommended for diagnosis because pneumonia or respiratory symptoms are often minimal or even absent in extrapulmonary manifestations due to M. pneumoniae infection. Concomitant use of immunomodulators, such as corticosteroids or immunoglobulins with antibiotics effective against M. pneumoniae, can be considered as treatment modalities for most severe cases, such as encephalitis. Further studies would be necessary to construct a comprehensive therapeutic strategy, covering microbiology (antibiotics), immunology (immunomodulators), and hematology (anticoagulants). The possible influence of the emergence of macrolide-resistant M. pneumoniae on extrapulmonary manifestations, which can be considered of limited clinical threat in Japan where the resistant rate has currently decreased, is discussed on the basis of unique biological characteristics of M. pneumoniae, the smallest self-replicating organism.

Mycoplasma pneumonia with persistent lymphadenopathy and severe cold agglutinin haemolysis

Mycoplasma pneumonia is an atypical pneumonia commonly affecting young patients with generally mild clinical course. We present a case of a 66-year-old female presenting with weight loss, night sweats and low-grade pyrexia. She acquired symptomatic haemolytic anaemia requiring blood transfusion, markedly raised erythrocyte sedimentation rate (ESR) to 114 mm/hr and extensive peri-hilar lymphadenopathy on computed tomography (CT) scan. After excluding malignancy and granulomatous diseases, she made good recovery although a 4 week follow-up CT scan showed persistent but resolving lymphadenopathy. We discuss the considerations for blood transfusion in cold agglutinin disease, and the investigations for immunological manifestations in Mycoplasma pneumonia.

Novel aspects on the pathogenesis of Mycoplasma pneumoniae pneumonia and therapeutic implications

Mycoplasma pneumoniae (Mp) is a leading cause of community acquired pneumonia. Knowledge regarding Mp pneumonia obtained from animal models or human subjects has been discussed in many different reports. Accumulated expertise concerning this critical issue has been hard to apply clinically, and potential problems may remain undiscovered. Therefore, our multidisciplinary team extensively reviewed the literature regarding Mp pneumonia, and compared findings from animal models with those from human subjects. In human beings, the characteristic pathological features of Mp pneumonia have been reported as alveolar infiltration with neutrophils and lymphocytes and lymphocyte/plasma cell infiltrates in the peri-bronchovascular area. Herein, we demonstrated the novel aspects of Mp pneumonia that the severity of the Mp pneumonia seemed to depend on the host innate immunity to the Mp, which might be accelerated by antecedent Mp exposure (re-exposure or latent respiratory infection) through up-regulation of Toll-like receptor 2 expression on bronchial epithelial cells and alveolar macrophages. The macrolides therapy might be beneficial for the patients with macrolide-resistant Mp pneumonia via not bacteriological but immunomodulative effects. This exhaustive review focuses on pathogenesis and extends to some therapeutic implications such as clarithromycin, and discusses the various diverse aspects of Mp pneumonia. It is our hope that this might lead to new insights into this common respiratory disease.

Sequentially appearing erythema nodosum, erythema multiforme and Henoch-Schönlein purpura in a patient with Mycoplasma pneumoniae infection: a case report

Introduction

A wide variety of skin manifestations are associated with Mycoplasma pneumoniae infection. However, the precise mechanisms by which M. pneumoniae infection is able to produce a variety of cutaneous manifestations are poorly understood.

Case presentation

An 8-year-old Japanese girl presented with sequential skin manifestations, including erythema nodosum, erythema multiforme and Henoch-Schönlein purpura. Although a chest radiograph showed no significant lung abnormalities, serological examinations revealed that these skin manifestations were associated with M. pneumoniae infection.

Conclusion

It has been reported that the variations in cutaneous manifestations of M. pneumoniae infection can be attributed to the immaturity of the adaptive immunity of a host. However, the case presented herein indicates that skin manifestations might not be specific for each individual. An awareness of the varied patterns of cutaneous disease is essential for the early diagnosis and treatment of patients with manifestations of M. pneumoniae infection.

Association of acute urticaria with Mycoplasma pneumoniae infection in hospitalized children

BACKGROUND

Acute urticaria is a common and disturbing disorder in children and has a versatile etiology.

OBJECTIVE

To investigate the association of acute urticaria with Mycoplasma pneumoniae infection in hospitalized children.

METHODS

Hospitalized children with acute urticaria from Taiwan who did not respond to antihistamine treatment and avoidance of food allergens were studied from February 1, 2006, to July 31, 2007. These patients with urticaria were compared with those who had other respiratory tract diseases and were classified into 2 groups: urticaria patients with and without M pneumoniae infection. The presence of M pneumoniae infection was determined by positive serologic findings.

RESULTS

Sixty-five patients with acute urticaria and 49 patients with other respiratory tract diseases were enrolled in this study. Patients with urticaria had significantly less febrile duration but significantly higher platelet and lymphocyte counts than those with other respiratory tract diseases. Of the 65 patients with urticaria, 21 (32%) showed serologic evidence of M pneumoniae infection. Patients with M pneumoniae-associated urticaria received azithromycin treatment and needed a shorter time for improvement (P = .01) and complete resolution (P = .04). The total IgE levels and the results of specific IgE tests were not significantly different between urticaria patients with and without M pneumoniae infection.

CONCLUSION

This study found that in Taiwan one-third of acute childhood urticaria leading to patient hospitalization was related to M pneumoniae infection. Therefore, children with urticaria who are not responding to antihistamine treatment and abstinence from food allergens should be encouraged to undergo serologic examinations for M pneumoniae to diagnose this antibiotic-responsive disorder.

Acute urticaria in children

The fine article, "First Attack of Acute Urticaria in a Pediatric Emergency Department" by Liu et at, which appeared in the June issue of Pediatrics and Neonatology prompted me to submit comments and a review on the subject of urticaria in children, because this is indeed a pediatric problem that is frequently seen in clinical practice.

The change of asthma-associated immunological parameters in children with Mycoplasma pneumoniae infection

BACKGROUND

Mycoplasma pneumoniae (M. pneumoniae), an atypical pathogen, is increasingly recognized as a common and important pathogen. Previous studies showed that M. pneumoniae infection may play a role in asthmatic mechanisms based on evidence collected from peripheral blood or sputum of patients or animal models. However, evidence reported from the airways of patients has been rare.

OBJECTIVE

To estimate the role of M. pneumoniae infection in asthma by measuring the immunological parameters from peripheral blood and bronchoalveolar lavage fluid (BALF) in pediatric patients with mycoplasma pneumonia.

METHODS

A total of 30 patients with mycoplasma pneumonia and 37 patients without M. pneumoniae infection undergoing fiberoptic bronchoscopy were reviewed. The peripheral blood cell count, immunoglobulins (Ig), BALF cell count, and other clinical and laboratory data were reviewed and analyzed.

RESULTS

There were significantly more patients with raised basophil counts in the M. pneumoniae group than that in the control group (p = 0.033). Serum immunoglobulin (Ig) A, IgM, and IgG levels in the M. pneumoniae group were significantly higher than those in the control group (p = 0.008, p = 0.011, and p = 0.019, respectively). The percentage of eosinophils in BALF cells was in the range 0 to 10% in M. pneumoniae patients, while it ranged between 0 and 4% in the control group with a significant difference (p = 0.043). In the M. pneumoniae group, we found that the percentage of eosinophils in the BALF cells was positively correlated with age, the percentage of peripheral eosinophils, and BALF lymphocytes (r = 0.298, p = 0.030; r = 0.341, p = 0.014; r = 0.387, p = 0.006; respectively) and negatively correlated with total peripheral white blood cell (r = -0.387, p = 0.005).

CONCLUSION

These results suggest that M. pneumonia infection is associated with the asthma mechanism, especially in older children.

An update on childhood urticaria and angioedema

PURPOSE OF REVIEW

The present review serves to address urticaria - both acute and chronic - as well as the differential diagnosis of urticarial syndromes in the pediatric population. We also wish to update the reader on progress in the pathophysiology, diagnosis and treatment of urticaria.

RECENT FINDINGS

Acute and chronic urticaria represent syndromes caused by a variety of triggers. Recent literature continues to describe subtypes of urticaria that may be differentially responsive to particular therapies. Recent associations highlight the need to fully evaluate patients for allergic and infectious triggers of urticaria. It is important to distinguish idiopathic urticaria from related conditions such as anaphylaxis, systemic conditions and autoimmune urticaria. Although antihistamines remain a cornerstone of therapy, particular urticaria subtypes may also respond to novel therapies such as omalizumab. Chronic urticaria has a significant impact on a patient's quality of life.

SUMMARY

Urticaria is a common condition. Our understanding of distinct urticaria subtypes differentially responsive to targeted therapies continues to increase. Due to the myriad of triggers that may cause urticaria, careful individualized patient assessment is necessary to exclude potential etiologies prior to a diagnosis of idiopathic urticaria.