Outbreaks of Middle East Respiratory Syndrome in Two Hospitals Initiated by a Single Patient in Daejeon, South Korea

BACKGROUND: A Middle East Respiratory Syndrome coronavirus (MERS-CoV) outbreak in South Korea in 2015 started by a single imported case and was amplified by intra- and inter-hospital transmission. We describe two hospital outbreaks of MERS-CoV infection in Daejeon caused by a single patient who was infected by the first Korean case of MERS. MATERIALS AND METHODS: Demographic and clinical information involving MERS cases in the Daejeon cluster were retrospectively collected and potential contacts and exposures were assessed. The incubation periods and serial intervals were estimated. Viral RNAs were extracted from respiratory tract samples obtained from the index case, four secondary cases and one tertiary case from each hospital. The partial S2 domain of the MERS-CoV spike was sequenced. RESULTS: In Daejeon, a MERS patient (the index case) was hospitalized at Hospital A in the first week of illness and was transferred to Hospital B because of pneumonia progression in the second week of illness, where he received a bronchoscopic examination and nebulizer therapy. A total of 23 secondary cases (10 in Hospital A and 13 in Hospital B) were detected among patients and caregivers who stayed on the same ward with the index case. There were no secondary cases among healthcare workers. Among close hospital contacts, the secondary attack rate was 15.8% (12/76) in Hospital A and 14.3% (10/70) in Hospital B. However, considering the exposure duration, the incidence rate was higher in Hospital B (7.7/100 exposure-days) than Hospital A (3.4/100 exposure-days). In Hospital B, the median incubation period was shorter (4.6 days vs. 10.8 days), the median time to pneumonia development was faster (3 days vs. 6 days) and mortality was higher (70% vs. 30.8%) than in Hospital A. MERS-CoV isolates from 11 cases formed a single monophyletic clade, with the closest similarity to strains from Riyadh. CONCLUSION: Exposure to the MERS case in the late stage (2nd week) of diseases appeared to increase the risk of transmission and was associated with shorter incubation periods and rapid disease progression among those infected. Early detection and isolation of cases is critical in preventing the spread of MERS in the hospital and decreasing the disease severity among those infected.

Clinical Presentation and Outcomes of Middle East Respiratory Syndrome in the Republic of Korea

BACKGROUND: From May to July 2015, the Republic of Korea experienced the largest outbreak of Middle East respiratory syndrome (MERS) outside the Arabian Peninsula. A total of 186 patients, including 36 deaths, had been diagnosed with MERS-coronavirus (MERS-CoV) infection as of September 30th, 2015. MATERIALS AND METHODS: We obtained information of patients who were confirmed to have MERS-CoV infection. MERS-CoV infection was diagnosed using real-time reverse-transcriptase polymerase chain reaction assay. RESULTS: The median age of the patients was 55 years (range, 16 to 86). A total of 55.4% of the patients had one or more coexisting medical conditions. The most common symptom was fever (95.2%). At admission, leukopenia (42.6%), thrombocytopenia (46.6%), and elevation of aspartate aminotransferase (42.7%) were observed. Pneumonia was detected in 68.3% of patients at admission and developed in 80.8% during the disease course. Antiviral agents were used for 74.7% of patients. Mechanical ventilation, extracorporeal membrane oxygenation, and convalescent serum were employed for 24.5%, 7.1%, and 3.8% of patients, respectively. Older age, presence of coexisting medical conditions including diabetes or chronic lung disease, presence of dyspnea, hypotension, and leukocytosis at admission, and the use of mechanical ventilation were revealed to be independent predictors of death. CONCLUSION: The clinical features of MERS-CoV infection in the Republic of Korea were similar to those of previous outbreaks in the Middle East. However, the overall mortality rate (20.4%) was lower than that in previous reports. Enhanced surveillance and active management of patients during the outbreak may have resulted in improved outcomes.

Multidrug-Resistant Gram-Positive Bacterial Infections / 대한내과학회지

Antimicrobial resistance threatens the effective treatment of bacterial infections and is a serious problem worldwide. Multidrug-resistant bacteria are difficult to treat and the treatment outcome is worse than with susceptible bacteria. In Korea, the antibiotic resistance rates of the major Gram-positive bacteria methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococcus (VRE), and penicillin-resistant Streptococcus pneumoniae (PRSP) are very high. Clinicians should know the risk factors for developing multidrug-resistant bacterial infection, update the changing local epidemiology of resistant bacteria, and choose appropriate antibiotics in clinical practice. The overuse and misuse of broad spectrum antibiotics should be avoided. This review focuses on the epidemiology and risk factors of MRSA, VRE, and PRSP, the major multidrug-resistant Gram-positive bacteria.

Benign Lymphoepithelial Cyst of the Parotid Gland as an Initial Manifestation of Human Immunodeficiency Virus Infection / 대한내과학회지

Benign lymphoepithelial cysts are rare, and are associated with swelling of the salivary glands (usually the parotid gland). The cytopathological features include lymphoid hyperplasia with an epithelial component, exhibiting cystic and proliferative changes. Development of a benign lymphoepithelial cyst commonly precedes acquisition of acquired immunodeficiency syndrome, but may also be the initial clinical manifestation of human immunodeficiency virus (HIV) infection. A 43 year-old male presented with a slowly growing multilocular cystic mass in his right cheek. Computed tomography of the neck revealed a well-circumscribed cystic lesion in the bilateral parotid glands. A provisional diagnosis of a benign lymphoepithelial cyst associated with HIV infection was made, and Western blotting confirmed the HIV infection. Three months after initiation of antiretroviral therapy, the parotid swelling was completely resolved. We report this case to suggest that clinicians should consider the possibility of HIV infection when patients present with benign lymphoepithelial cysts of the parotid gland.

Severe Form of Persistent Thebesian Veins Presenting as Ischemic Heart Disease

Coronary artery fistula is a rare congenital anomaly. Most patients with this anomaly are asymptomatic, but some may develop heart failure, myocardial ischemia or arrhythmias. We report a case of a patient who presented with myocardial ischemia secondary to persistent Thebesian veins. Coronary angiography demonstrated a marked capillary blush draining into the left ventricular cavity through multiple microfistulae from the left anterior descending artery, left circumflex artery and right coronary artery. The patient was discharged without chest pain and was medically maintained with a beta-blocker and angiotensin converting enzyme inhibitor.

Avascular Necrosis of Femoral Head in HIV-infected Patients: Case Reports and Review of the Literature

After introduction of highly active antiretroviral therapy, the incidence of opportunistic infections and malignancies in HIV patients decreased. On the other hand, several osteoarticular complications are increasingly reported. Avascular necrosis of femoral head is one of such complications. HIV-infected patients have an 100-fold increased risk of avascular necrosis of femoral head compared to the general population. Many risk factors for this debilitating complication have been suggested. This paper reports five cases of avascular necrosis of femoral head in HIV-infected patients with review of literature.

An Outbreak of Trichinellosis with Detection of Trichinella Larvae in Leftover Wild Boar Meat

The clinical diagnosis of trichinellosis can be difficult due to lack of pathognomonic signs or symptoms. In Korea, since the first report of human infection by Trichinella spiralis in 1997 following the consumption of raw badger meat, there have been occasional trichinellosis outbreaks. We describe an outbreak of 12 cases of trichinellosis in Korea and implicate raw wild boar meat as the culprit. A total of 27 larvae of Trichinella (0.54 larvae per gram of meat) were recovered from the leftover raw wild boar meat.