Live enteroviruses, but not other viruses, detected in human pancreas at the onset of type 1 diabetes in the DiViD study

AIMS/HYPOTHESIS

Enterovirus (EV) infection of pancreatic islet cells is one possible factor contributing to type 1 diabetes development. We have reported the presence of EV genome by PCR and of EV proteins by immunohistochemistry in pancreatic sections. Here we explore multiple human virus species in the Diabetes Virus Detection (DiViD) study cases using innovative methods, including virus passage in cell cultures.

METHODS

Six recent-onset type 1 diabetes patients (age 24-35) were included in the DiViD study. Minimal pancreatic tail resection was performed under sterile conditions. Eleven live cases (age 43-83) of pancreatic carcinoma without diabetes served as control cases. In the present study, we used EV detection methods that combine virus growth in cell culture, gene amplification and detection of virus-coded proteins by immunofluorescence. Pancreas homogenates in cell culture medium were incubated with EV-susceptible cell lines for 3 days. Two to three blind passages were performed. DNA and RNA were extracted from both pancreas tissue and cell cultures. Real-time PCR was used for detecting 20 different viral agents other than EVs (six herpesviruses, human polyomavirus [BK virus and JC virus], parvovirus B19, hepatitis B virus, hepatitis C virus, hepatitis A virus, mumps, rubella, influenza A/B, parainfluenza 1-4, respiratory syncytial virus, astrovirus, norovirus, rotavirus). EV genomes were detected by endpoint PCR using five primer pairs targeting the partially conserved 5' untranslated region genome region of the A, B, C and D species. Amplicons were sequenced. The expression of EV capsid proteins was evaluated in cultured cells using a panel of EV antibodies.

RESULTS

Samples from six of six individuals with type 1 diabetes (cases) and two of 11 individuals without diabetes (control cases) contained EV genomes (p<0.05). In contrast, genomes of 20 human viruses other than EVs could be detected only once in an individual with diabetes (Epstein-Barr virus) and once in an individual without diabetes (parvovirus B19). EV detection was confirmed by immunofluorescence of cultured cells incubated with pancreatic extracts: viral antigens were expressed in the cytoplasm of approximately 1% of cells. Notably, infection could be transmitted from EV-positive cell cultures to uninfected cell cultures using supernatants filtered through 100 nm membranes, indicating that infectious agents of less than 100 nm were present in pancreases. Due to the slow progression of infection in EV-carrying cell cultures, cytopathic effects were not observed by standard microscopy but were recognised by measuring cell viability. Sequences of 5' untranslated region amplicons were compatible with EVs of the B, A and C species. Compared with control cell cultures exposed to EV-negative pancreatic extracts, EV-carrying cell cultures produced significantly higher levels of IL-6, IL-8 and monocyte chemoattractant protein-1 (MCP1).

CONCLUSIONS/INTERPRETATION

Sensitive assays confirm that the pancreases of all DiViD cases contain EVs but no other viruses. Analogous EV strains have been found in pancreases of two of 11 individuals without diabetes. The detected EV strains can be passaged in series from one cell culture to another in the form of poorly replicating live viruses encoding antigenic proteins recognised by multiple EV-specific antibodies. Thus, the early phase of type 1 diabetes is associated with a low-grade infection by EVs, but not by other viral agents.

Electron Microscopy Revealed Massive Lipid Droplets in Cardiomyocytes in a Patient with Cardiogenic Shock Following a Fulminant Type 1 Diabetes Mellitus

A 52-year-old man with consciousness disorder following a 2-day history of general fatigue, diarrhea, vomiting and excessive thirst was admitted to our hospital. Severe hyperglycemia (1,739 mg/dL) with a slightly elevated HbA1c level (6.9%), ketonuria and low C-peptide level (0.07 ng/mL) confirmed the diagnosis of fulminant type 1 diabetes mellitus (FT1DM). Following sudden unexplained cardiogenic shock shortly after the initiation of insulin therapy with no evidence of myocardial ischemia assessed by coronary angiography, the patient was supported with percutaneous venoarterial extracorporeal membrane oxygenation. Electron microscopic analysis of the myocardium revealed massive lipid droplets without the infiltration of inflammatory cells. His left ventricular function began to recover during the following days and returned to a normal level on day 14. Currently, the impact of FT1DM on intramyocardial lipid deposition is poorly understood. However, this case suggests that even short-term exposure to high concentrations of glucose can be responsible for lipotoxicity followed by severe cardiac dysfunction.

A rare case of fulminant type 1 diabetes mellitus accompanied by both acute pancreatitis and myocarditis - case report

BACKGROUND

Fulminant type 1 diabetes mellitus (FT1D) is a newly established subtype of type 1 diabetes. Its etiology has not been fully elucidated. Several cases with FT1D have exhibited pancreatitis or myocarditis.

CASE PRESENTATION

We report a 31-year-old Japanese woman who showed upper abdominal pain and was admitted to a local hospital. She was initially diagnosed with acute pancreatitis based on serum amylase elevation and swelling of the pancreas on computed tomography. Four days after admission, she developed diabetic ketoacidosis and was transferred to our hospital. Her symptoms and laboratory findings met the FT1D criteria. On the 3rd hospital day, electrocardiography (ECG) showed ST-segment elevation, and serum cardiac enzymes were markedly elevated. Because she exhibited late gadolinium enhancement in the apical wall on contrast-enhanced cardiac magnetic resonance imaging, she was diagnosed as acute myocarditis. Abnormal ECG findings and elevations of biomarkers associated with myocarditis showed improvement on the next day.

CONCLUSIONS

This is the first case of FT1D accompanied by both pancreatitis and myocarditis and suggests that the pathophysiology of FT1D is related to the common etiology of acute pancreatitis and myocarditis.

Arrhythmias in myocarditis: State of the art

Many kinds of arrhythmias may occur in patients with myocarditis at any stage of the disease. However, compared to the other clinical presentations, arrhythmic myocarditis has been poorly described in the literature. Arrhythmias occurring in either ongoing or previous myocardial inflammation are complex and heterogeneous, and the disease itself is often underdiagnosed, thus limiting data collection and interpretation. However, different from the other clinical presentations, arrhythmic myocarditis requires specific diagnostic, prognostic, and therapeutic considerations. The aim of this review is to critically summarize the state of the art on myocarditis presenting with arrhythmias in terms of epidemiology, etiology, diagnosis, prognosis, and treatment.

Parainfluenza 3 Respiratory Infection Associated with Pericardial Effusion in a Very Low Birthweight Infant

Parainfluenza 3 virus is a frequent cause of respiratory infections in the pediatric population although it is uncommonly diagnosed in neonates, being usually reported as neonatal intensive care unit microepidemics. We report a case of parainfluenza 3 respiratory infection associated with pericardial effusion in a very low birthweight infant.

Fulminant Type 1 Diabetes Mellitus Associated with Coxsackie Virus Type A2 Infection: A Case Report and Literature Review

A 65-year-old Japanese man presented to our hospital in June 2013 with a 6-day history of fever and fatigue, a 24-h history of thirst, and polyuria. His temperature was 37.8°C and he was alert. However, laboratory tests revealed severe hyperglycemia, undetectable C-peptide levels, and diabetic ketoacidosis. Serum antibody testing confirmed a Coxsackie virus A2 infection. A variety of viral infections are reported to be involved in the development of fulminant type 1 diabetes mellitus (FT1D). Our patient is the first reported case of FT1D associated with Coxsackie virus A2 infection and supports the etiological role of common viral infections in FT1D.

New-Onset Myocarditis in an Immunocompetent Adult with Acute Metapneumovirus Infection

Introduction. A number of viruses have been implicated in viral myocarditis; however, there has been no previous report of human metapneumovirus (hMPV) causing this condition. Discovered in 2001, hMPV is typically associated with upper respiratory illness, mainly affecting children. Case Presentation. We report the case of a 25-year-old man with acute systolic heart failure from viral myocarditis secondary to the hMPV. The patient was initially admitted to the general medical ward but developed increasing oxygen requirements resulting in transfer to the cardiac intensive care unit. Cardiac magnetic resonance imaging was used to help confirm the diagnosis. He was treated with intravenous diuretics, and afterload and preload agents, and he was subsequently discharged home after seven days of hospitalization. Discussion. hMPV is typically a respiratory pathogen; however, it was associated with in myocarditis in our patient. Due to the recent ability to detect this virus, we may see more cases of this, particularly during peak months of infection. Conclusion. This is the first case description of myocarditis associated with hMPV infection.