Complete heart block due to diphtheritic myocarditis in the present era

Diphtheria's Dual Threat: Amplifying Awareness of Cardiac Complications for Enhanced Intervention

Even though immunization can prevent illness, diphtheria, which is caused by toxic strains of Corynebacterium diphtheriae, remains a serious public health risk. Although the worldwide incidence has declined, it still poses a serious hazard in developing countries, such as Pakistan, where new data suggest an increase in cases. A significant proportion of patients with respiratory diphtheria experience cardiac complications, specifically myocarditis, which carries a high death risk of 50% to 75%. The diphtheria toxin's affinity for cardiac tissues is the cause of these consequences, which include arrhythmias and myocardial dysfunction. Recent studies from Lady Reading Hospital in Peshawar show the seriousness of the situation, with 73 patients presenting with cardiac complications in just one year, resulting in a devastating fatality rate despite early management. This highlights the pressing need for increased awareness and all-encompassing immunization campaigns, particularly for children who have received insufficient vaccinations. Timely vaccination and booster doses are critical for reducing myocarditis-related mortality, mandating prioritizing immunization efforts to defend susceptible populations globally.

Diphtheria-Associated Myocarditis: Clinical Profiles and Mortality Trends in a Tertiary Care Hospital in Pakistan

BACKGROUND

Corynebacterium diphtheriae infection, causing diphtheria, is a public health concern, particularly in developing nations like Pakistan. Despite immunization efforts, recent outbreaks since 2022 have emphasized the continuing threat. This study focuses on describing the clinical characteristics of children with diphtheria-induced myocarditis and exploring the association between early cardiac abnormalities, future fatality rates, and contributing factors.

METHODS

A one-year cross-sectional study was undertaken at Lady Reading Hospital MTI Peshawar, encompassing 73 pediatric patients diagnosed with diphtheria-associated myocarditis. Data, including demographic characteristics, cardiac enzymes, and serial ECG and echocardiography data, were gathered from the health management information system (HMIS). Institutional Ethical Committee approval was obtained, and informed consent was waived due to its retrospective nature.

RESULTS

Gender distribution within the study was balanced, with 35 males (47.9%) and 38 females (52.1%). ECG data revealed various prevalence rates: 27.4% for rhythm abnormalities, 20% for conduction abnormalities, 6.8% for ischemia alterations, and 20.5% for normal findings. Treatment measures included anti-diphtheria serum (ADS) in 87.7% and temporary pacemaker placement (TPM) in 13.7% of patients. Echo findings indicated a variety of cardiac dysfunctions: 53.4% with no dysfunction, 9.6% mild malfunction, 6.8% with moderate dysfunction, and 30.1% with severe dysfunction. The categorization of creatine kinase (CK), lactate dehydrogenase (LDH), and troponin I (Trop I) gave insights into the biochemical aspects.

CONCLUSION

This study gives a full insight into the clinical symptoms of diphtheria-induced myocarditis in children. The findings can help establish a foundation for ongoing study into potential gender-related trends in clinical outcomes, contributing to improved care and preventative methods.

Diphtheritic myocarditis: a case report, with toxinmediated complications and multi-organ involvement

The re-emergence of diphtheria in South Africa in recent years warns of incomplete vaccination coverage. Recent outbreaks have been associated with a high mortality rate, due to late presentation, limited access to antitoxin and the occurrence of serious systemic complications. Death due to diphtheria is most commonly associated with diphtheritic myocarditis, which presents with heart failure, cardiogenic shock and conduction abnormalities. This case highlights the key clinical features and systemic complications, and examines the reasons for the return of diphtheria in our community.

Knowledge of Silesia adult inhabitants regarding preventive vaccinations effect on cardiovascular diseases

OBJECTIVES

Protective vaccinations are important in maintaining health and reducing suffering from infectious diseases. Also, vaccine-preventable infectious diseases are associated with the development and progression of cardiovascular diseases.

AIM

The study aimed to test adults' knowledge of the role of protective vaccinations in the prevention of cardiovascular diseases, and their opinions on the quantity of the information provided by doctors in this regard.

METHODS

A total of 700 adults participated in the study, most of whom were women (500; 71.43%). The study used an original questionnaire containing questions covering vaccinations and cardiovascular diseases, and the general characteristics of the participants. The inclusion criteria for the study were 18 years of age and written informed consent to participate in the study.

RESULTS

Over 60% of the participants did not know of, or denied the possibility of, developing cardiovascular diseases as a result of avoiding required preventive vaccinations. More than half of the participants stated that there is no need to recommend influenza vaccination to patients with cardiovascular diseases. Over 70% of participants stated that family doctors did not provide sufficient information about protective vaccinations.

CONCLUSION

In these adults, knowledge of the role of preventive vaccinations in the prevention of cardiovascular diseases was low, and the quantity of the information provided by doctors about preventive vaccinations were considered to be insufficient. Public awareness of the effects of avoiding preventive vaccinations should be raised especially among people with CVD.

Fatal diphtheria myocarditis in a 3-year-old girl-related to late availability and administration of antitoxin?

Sporadic cases of diphtheria are very rare throughout Europe. A 3-year-old incompletely vaccinated girl was admitted with pharyngotonsillitis caused by diphtheria. On day 9 of her illness, renal and cardiac failure with a third-degree AV-block occurred. Unfortunately, she died within 36 h of admission to intensive care, despite pacemaker placement, the administration of antibiotics and diphtheria antitoxin. The delayed antitoxin administration 7 days after admission to hospital was related to a lack of availability and knowledge of its availability in Europe and this is likely to have contributed to the unfavourable outcome.

Potency of a human monoclonal antibody to diphtheria toxin relative to equine diphtheria anti-toxin in a guinea pig intoxication model

Prompt administration of anti-toxin reduces mortality following Corynebacterium diphtheriae infection. Current treatment relies upon equine diphtheria anti-toxin (DAT), with a 10% risk of serum sickness and rarely anaphylaxis. The global DAT supply is extremely limited; most manufacturers have ceased production. S315 is a neutralizing human IgG1 monoclonal antibody to diphtheria toxin that may provide a safe and effective alternative to equine DAT and address critical supply issues. To guide dose selection for IND-enabling pharmacology and toxicology studies, we dose-ranged S315 and DAT in a guinea pig model of diphtheria intoxication based on the NIH Minimum Requirements potency assay. Animals received a single injection of antibody premixed with toxin, were monitored for 30 days, and assigned a numeric score for clinical signs of disease. Animals receiving ≥ 27.5 µg of S315 or ≥ 1.75 IU of DAT survived whereas animals receiving ≤ 22.5 µg of S315 or ≤ 1.25 IU of DAT died, yielding a potency estimate of 17 µg S315/IU DAT (95% CI 16–21) for an endpoint of survival. Because some surviving animals exhibited transient limb weakness, likely a systemic sign of toxicity, DAT and S315 doses required to prevent hind limb paralysis were also determined, yielding a relative potency of 48 µg/IU (95% CI 38–59) for this alternate endpoint. To support advancement of S315 into clinical trials, potency estimates will be used to evaluate the efficacy of S315 versus DAT in an animal model with antibody administration after toxin exposure, more closely modeling anti-toxin therapy in humans.

Corynebacterium ulcerans cutaneous diphtheria

We describe the case of a patient with cutaneous diphtheria caused by toxigenic Corynebacterium ulcerans who developed a right hand flexor sheath infection and symptoms of sepsis such as fever, tachycardia, and elevated C-reactive protein, after contact with domestic cats and dogs, and a fox. We summarise the epidemiology, clinical presentation, microbiology, diagnosis, therapy, and public health aspects of this disease, with emphasis on improving recognition. In many European countries, C ulcerans has become the organism commonly associated with cutaneous diphtheria, usually seen as an imported tropical disease or resulting from contact with domestic and agricultural animals. Diagnosis relies on bacterial culture and confirmation of toxin production, with management requiring appropriate antimicrobial therapy and prompt administration of antitoxin, if necessary. Early diagnosis is essential for implementation of control measures and clear guidelines are needed to assist clinicians in managing clinical diphtheria. This case was a catalyst to the redrafting of the 2014 national UK interim guidelines for the public health management of diphtheria, released as final guidelines in March, 2015.

Diphtheria in Andhra Pradesh-a clinical-epidemiological study

OBJECTIVES

Clinical diphtheria is on the increase worldwide, mainly affecting developing countries. We sought to understand its presentation among patients at Sir Ronald Ross Institute of Tropical and Communicable Diseases in Hyderabad, Andhra Pradesh, India.

METHODS

Diphtheria patients presented with fever, pharyngitis, and a patch in the throat. Data collected for each patient included age, clinical presentation, morbidity, mortality, bacteria isolated from culture, and immunization status.

RESULTS

Of 61 950 admissions from January 2008 to December 2012, 2925 (4.7%) had clinical diphtheria; 1194 had been immunized and 1731 were non-immunized. Immunized patients had a milder disease. Culture-positive immunized patients were positive for Corynebacterium other than diphtheriae (COD; n=104) or Corynebacterium diphtheriae (CD; n=23); these patients suffered mild disease and recovered completely. In contrast, culture-positive non-immunized patients were positive for COD (n=11) or CD (n=412). Eighty-one patients (3%) died, 77 of whom were non-immunized; death was usually as a result of myocarditis. Seventy-three percent of deaths were in patients aged <5 years.

CONCLUSIONS

The clinical presentation of diphtheria and its severity and morbidity differ considerably in immunized and non-immunized patients. Disease caused by CD can be deadly, while disease due to COD is mild and responds to treatment.