False-positive troponin I in a patient with acute cholecystitis and positive rheumatoid factor assay

Acute Cholecystitis Leading to Elevated High-Sensitive Cardiac Troponin I in a Young Female Without Any Cardiac Ailment: A Rare Case Presentation

Cardiac troponin I (cTnI) is regarded as a gold standard investigation for the diagnosis of acute myocardial infarction (AMI). However, cTnI may be elevated in certain non-AMI cardiac conditions and even in certain noncardiac conditions. We report a case of a young female presenting with symptoms suggestive of acute cholecystitis with elevated high-sensitive cardiac troponin I (hs-cTnI). The patient developed acute chest pain during the hospital stay. On evaluation, quantitative assay for hs-cTnI was found to be elevated; however, other markers of cardiac damage such as creatinine kinase-MB (CK-MB), qualitative cTnI by card test, and even echocardiogram (ECG) were found to be negative. As the patient was a young female with no significant history of coronary diseases, the spurious elevation of hs-TnI due to a noncardiac ailment was suspected. The patient was managed with minimal cardiological management till AMI was excluded. The hs-cTnI levels returned to normal post-cholecystectomy. A patient presenting with symptoms suggestive of cholecystitis and elevated hs-cTnI must be carefully evaluated before resorting to any invasive management for AMI. In most cases, hs-cTnI will return to normal post-cholecystectomy.

Pseudo-Wellens' syndrome and intermittent left bundle branch block in acute cholecystitis

We present a case of a 54-year-old male patient who was admitted to our Emergency Department (ED) with localized epigastric pain. Inflammation markers, ultrasound, and CT scan were inconsistent with an initial diagnosis of cholecystitis. However, there was additional evidence of cholecystolithiasis. The ECG showed new anterior biphasic T waves typical for a Wellens' type A ECG. Additionally, the patient had an intermittent left bundle branch block (LBBB). The diagnostic challenges in differentiating possible diagnoses will be described, to which in this case, were either acute cholecystitis or acute coronary syndrome (ACS). A laparoscopic study confirmed acute cholecystitis. Coronary angiography showed no pathological processes associated with ACS. ECG abnormalities were initially ongoing, but were no longer detectable during an 8month follow up assessment.

Acute cholecystitis and myocardial infarction: a case study with coronary involvement

Possible links between inflammatory stimuli and atherothrombotic disease in the context of gallbladder pathology are not well understood. Our case demonstrates that clinical suspicion of cardiac disease after a diagnosis of acute cholecystitis should remain high in light of the dire consequences of a missed diagnosis.

False Positive Troponin Levels due to Heterophil Antibodies in a Pregnant Woman

Positive troponin test results in peripheral blood can be detected either during myocardial injury or from falsely positive test results. In this report, we present the positive results of a troponin test in a 24-year-old pregnant woman referred to the emergency department with atypical chest pain, and the clinical algorithm that we used to make the correct diagnosis. This patient presented with the same complaint of chest pain at different times while positive troponin levels were detected. In the absence of signs of myocardial injury, we suspected that heterophil antibodies were playing a major role. Further examinations revealed heterophil antibodies that could cross react with the troponin tests in peripheral blood.

Electrocardiographic changes and false-positive troponin I in a patient with acute cholecystitis

Cardiac troponins are the most sensitive and specific serum markers of myocardial cell injury, but they can also arise without apparent cardiac injury. Besides, acute cholecystitis may be associated with nonspecific ST-T wave changes in electrocardiography (ECG). The signs and symptoms of gallbladder and heart disease may overlap, which can make diagnosis difficult. We describe the case of a 75-year-old woman with clinical features suggestive of acute cholecystitis associated with transient ST segment elevation and elevated troponin I that, after extensive workup, did not seem to be attributable to myocardial ischemia or any other acute cardiac problem, but were exclusively related to cholecystitis. We show that cholecystitis with gallbladder distension can be the sole cause of pathological ECG changes and an increased troponin I level; this should be considered when evaluating patients with similar presentations.

The importance of analytical quality specifications for biomarker assays currently used in acute cardiac care

It is very important that cardiac biomarkers on which clinically relevant decisions will rest are measured with highly reliable assays. Adequate studies are needed before new methods can be implemented in the laboratory routine, and only well-documented assays should be considered for clinical use. Therefore, it is critical that, as new biomarkers are proposed, quality specifications are developed. Only after appropriate analytical quality specifications are addressed, the issues pertaining to methodological differences that result in non-harmonized concentration values, and clinical interpretation of biomarker concentrations will be reconciled. Today, the technology to address many analytic problems is at hand, but commitment on the part of manufacturers and their customers in the laboratory and clinical communities is essential. The design control loop is not closed until the finished in vitro diagnostic system is adequately validated to meet the customer needs, including analytical quality specifications. It is essential to determine the attributes and performance characteristics of relevant competitive systems and their degree of acceptance by clinical laboratories in order to demonstrate that user needs are definitely met. The responsibility of defining and implementing these issues must be a shared responsibility among laboratorians, clinicians, industry, and regulatory agencies on an international front. To date, two sets of quality specifications have been published, one for cardiac troponin assays and one for B-type natriuretic peptide assays. Both address analytical factors, such as calibrator characterization, antibody specificity, assay sensitivity and imprecision, and interferents, as well as preanalytical factors, such as sample type and stability. It would be ideal if regulatory agencies, such as FDA in the United States, accept these criteria for premarket approval clearance applications.

[Cardiac troponin I and T: specific biomarkers of cardiomyocyte]

PURPOSE

Cardiac troponin I and troponin T have replaced creatine kinase MB (CK-MB) for the diagnosis of cardiomyocyte necrosis. Cardiac specificity of these new markers leads to a change in our practice.

CURRENT KNOWLEDGE AND KEY POINTS

Following necrosis, intracellular proteins are released into blood. This easy concept overlaps a biological complexity since troponins are released as complexes leading to various cut-off values depending on the assay used, as least for cardiac troponin I. The increase in both specificity and analytical sensitivity of these markers reached to propose a new definition of myocardial infarction. The diagnosis of acute coronary syndrome is a clinical based diagnosis, the use of troponin contributing to their classification. Finally, pathological processes leading to cardiac injury may induce an increase in the cardiac troponin level.

FUTURE PROSPECTS AND PROJECTS

Troponin standardization is a challenge for the near future leading to better follow-up of patients and comparison between cohorts.