Monoclonal gammopathy (MG) encompasses a diverse group of disorders characterized by the secretion of monoclonal immunoglobulins or their light-chain components. The incidence of multiple myeloma (MM) in South Korea is rapidly increasing, and it is important to be aware of its initial clinical presentations and the most efficient laboratory algorithms for early detection. Serum protein electrophoresis (SPE) and urine protein electrophoresis (UPE) are the primary screening tests for patients with clinically suspected MM or amyloid light-chain amyloidosis; these tests are reimbursed in South Korea. We reviewed clinical studies that applied national and international guidelines to evaluate test panels for early detection of MGs, including MM. The serum free light chain (sFLC) with SPE panel is recommended for the initial work up for diagnosis of MGs. In the case of a normal SPE, sFLC should be measured subsequently, so as not to miss the presence of M-protein. Use of this screening panel avoids medical expenses related to delayed diagnosis. Guidelines and recommendations suggest that no single method (SPE, serum immunofixation electrophoresis, sFLC, or UPE) should be used to exclude a diagnosis of MM. We believe that a screening test panel comprising SPE plus sFLC will increase the rate of early and accurate diagnosis of MM and related disorders. (Korean J Med 2021;96:371-381)

The prevalence of atrial fibrillation (AF) is gradually increasing with the aging of the population, and there is also increasing interest in AF with the development of various single-lead electrocardiography measurement methods for diagnosis. Further, the current diagnosis and treatment policies for AF do not reflect its progression and complexity. In addition, the various factors related to AF diagnosis and treatment are not simple due to the diversification of tools, advances in treatment methods, and complex mechanism of AF. Therefore, there are many challenges to developing a simple AF classification system. To overcome these, there have been a number of attempts to systematically characterize AF according to treatment and prognosis rather than using a uniform classification. Further, as mentioned in the previous AF guidelines, further research is being conducted on an integrated patient-physician approach to AF. Such an approach would be the basis for consistent treatment based on the guidelines, and would help to improve patient outcomes. Further, for the integrated management of AF patients, some changes should be made to the current approach to develop a multidisciplinary approach, including changes to the behavior of team members, patients, their family members, and physicians. The Korean Heart Rhythm will introduce an integrated approach to the classification and structure of AF management, and provide guidelines for its application in clinical practice. (Korean J Med 2021;96:382-389)

The most important thing for the management of drug susceptible pulmonary tuberculosis is to diagnose active pulmonary tuberculosis as soon as possible and prevent the occurrence of new patients through appropriate treatment. Therefore, it should be a priority to quickly detect tuberculosis mycobacterium and quickly exclude drug-resistant tuberculosis before treatment begins. To this end, recent guidelines recommend the general use of Mycobacterium tuberculosis (MTB) polymerase chain reaction (PCR) tests, Xpert MTB/RIF tests, and rapid sensitivity tests through line probe assay (LPA). In addition, if the results of the test are positive, it is important to establish an in-hospital reporting system so that rapid reporting can be made. The treatment principle for drug susceptible pulmonary tuberculosis is 2 months of initial intensive phase (isoniazid, rifampin, ethambutol, pyrazinamide) followed by 4 months of maintenance phase (isoniazid, rifampin). Despite global efforts to shorten the duration of the treatment, the treatment of drug susceptible pulmonary tuberculosis has not changed for more than 35 years, and problems such as increased side effects and reduced drug adherence are serious obstacles to tuberculosis management. Therefore, efforts have been steadily made to shorten the treatment period through the combination of new drugs worldwide, and after many failures, they are finally paying off. A recently published Study 31/A5349 study found that 4 months short-term regimen using rifapentine (RPT) and moxifloxacin (MFX) demonstrated non-inferiority in existing standard regimen, as the result, a revision of World Health Organization guidelines is scheduled that 4 months short-term regimen using RPT and MFX may be an alternative. However, it is unlikely that RPT/MFX 4 months short-term regimen will be applied immediately in Korea because the use of RPT is currently limited in Korea due to the high frequency of side effects. (Korean J Med 2021;96:390-399)

Adult growth hormone (GH) deficiency is associated with insulin resistance, elevated cardiovascular risk profile, increased fat mass, reduced muscle mass, skeletal fragility, and impaired quality of life. GH replacement therapy improves body composition, exercise capacity, skeletal health, cardiovascular outcomes, and quality of life, while reducing mortality. Prior to initiation of GH replacement therapy, it is essential to diagnose GH deficiency via a GH stimulation test in adults suspicious of such deficiency. Therapy should be started using (individualized) low dose of GH, followed by titration to the normal range of insulin-like growth factor-1. Clinical improvements should be monitored and side effects should be minimized. (Korean J Med 2021;96:400-407)

Cancer of unknown primary (CUP) is a heterogenous group of cancers for which the anatomical site of origin is unidentifiable on the basis of standard evaluation and imaging. CUPs account for 2-5% of all malignancies and are characterized by early metastatic dissemination, aggressive clinical course, and poor response to palliative chemotherapy. It is important to identify favorable-risk CUP patients (10-20%), as they harbor chemo-sensitive and potentially curable tumors, and may require long-term disease control. Empirical combination chemotherapy has traditionally been the standard first-line therapy for most patients (80-90%), who do not belong to favorable-risk subsets; however, this approach has only modest benefits, with a median overall survival of < 1 year. Evidence supporting the clinical use of molecular tissue of origin (TOO) tests is still lacking. Two recent randomized clinical trials failed to show the benefit of TOO-based site-specific therapy over empirical chemotherapy. In an era of precision medicine, the use of comprehensive molecular profiling will provide opportunities to identify patient subsets who are susceptible to targeted therapies and immunotherapies. (Korean J Med 2021;96:408-414)

바이러스 감염의 신속하고 정확한 검사는 바이러스의 진단과 치료, 그리고 환자격리에 매우 중요하다. 바이러스 감염 진단을 위한 신속검사로 다양한 신속유전자검사, 신속항원검사, 신속항체검사 제품이 개발되어 이용되고 있다. 본고에서는 현재 국내에서 사용되고 있는 신속바이러스검사법의 종류와 원리, 검사 종목, 신속검사의 결과 해석 시 주의할 점에 대해서 알아보았다.

Rapid and accurate diagnostic tests for viral infections are essential for diagnosis, treatment, and patient isolation. Various rapid nucleic acid tests, rapid antigen tests, and rapid antibody tests have been developed and used to diagnose viral infections. In this paper, the types and characteristics of various rapid viral tests currently used in Korea, test items, and considerations when interpreting rapid test results are described. (Korean J Med 2021;96:415-420)

목적: 단일 상급종합병원에 보고된 1차 항결핵제의 약물이상반응 정보를 통해 한국인에서 항결핵제 약물이상반응 발생 현황을 파악하여 향후 결핵 관리를 위한 약물이상반응 대책 수립에 활용한다.
방법: 2009년부터 2018년까지 3차 의료기관에서 1차 항결핵제인 이소니아지드, 리팜핀, 에탐부톨, 피라진아미드를 처방 받은 환자들에 대해 원내 보고된 약물이상사례 데이터베이스를 기반으로 약물이상반응 정보를 수집하였고 약물이상반응이 발생한 환자의 나이, 성별, 총 치료 기간과 약물이상반응의 발생시점, 장기별 분류, 중증도 및 심각도 등을 분석하였다.
결과: 항결핵제를 처방 받은 5,482명 중 1,606명(29.3%)에서 약물이상반응이 보고되었고, 한 환자에서 1건에서 많게는 5건까지 총 2,098건의 약물이상반응이 보고되었는데, 경증이 680건(32.4%), 중등증이 1,282건(61.1%), 중증이 136건(6.5%)이었고 심각한 약물이상반응은 127건(6.1%)이었다. 1차 항결핵제에 의한 약물이상반응의 발생 장기별 분포는 피부 및 부속기관 장애가 27.5%로 가장 많았고, 위장관계 장애(17.5%)와 간 및 담도계 질환(13.1%)이 그 뒤를 이었다. 처방 건 당 이상반응 보고는 피라진아미드가 29.6%(1,406건/4,757명)로 가장 높았다. 중증 약물이상반응은 간 및 담도계 질환이, 심각한 약물이상반응의 경우 전신적 질환이 가장 많이 보고되었다. 총 치료 기간을 비교한 결과 약물이상반응이 발생하지 않았던 군은 224.0 ± 3.1일, 약물이상반응이 발생하였던 군은 247.0 ± 4.7일로 약물이상반응이 발생한 군이 통계적으로 유의하게 치료 기간이 평균 23일 정도 길었다(p = 0.009).
결론: 10년 동안 단일의료기관에서 수집된 1차 항결핵제의 약물이상반응 발생률은 29.3%였으며 중증반응도 6.5%로 적지 않게 발생하였다. 약물이상반응이 발생한 경우 치료 기간이 길어지거나 투약을 완료하지 못하는 경우가 생기는 등 치료의 진행에 영향을 미칠 수 있으므로 주의를 요한다.

Background/Aims: Tuberculosis has incidence and mortality rates that are among the highest for all communicable diseases. Adverse drug reactions (ADRs) to anti-tubercular drugs are common, and have a major impact on treatment maintenance and prognosis. It is important to understand the characteristics of ADRs and establish a suitable management plan.
Methods: We retrospectively reviewed patients with ADRs during treatment with first-line antitubercular drugs such as isoniazid, rifampicin, ethambutol, and pyrazinamide from 2009 to 2018. Age, sex, and total treatment period, and the onset, severity, seriousness, and system organ class of ADRs, were analyzed to understand the characteristics of first-line anti-tubercular drug-related ADRs.
Results: A total of 1,606 of 5,482 patients (29.3%) experienced ADRs after administration of first-line anti-tubercular drugs. The incidence of ADRs related to isoniazid, rifampicin, ethambutol, and pyrazinamide was 22.2%, 21.3%, 24.5%, and 29.6%, respectively. A total of 2,098 ADR reports were made (mean of 1.3 ± 0.6 per patient). The rates of mild, moderate, and severe ADRs were 32.4%, 61.1%, and 6.5%, respectively. There were 127 reports (6.1%) of serious ADRs. Skin and appendage disorders were most frequently reported (27.5%), followed by gastrointestinal disorders (17.5%), and liver and biliary system disorders (13.1%). The total treatment period was longer in patients who experienced ADRs (224.0 ± 3.1 days vs. 247.0 ± 4.7 days, p = 0.009).
Conclusions: The incidence of ADRs to first-line anti-tuberculosis drugs was 29.3%, and 6.5% were severe ADRS. ADRs prolonged the overall treatment duration, indicating the importance of their detection and management. (Korean J Med 2021;96:421-431)

당뇨병성 케톤산증 환자는 QT 간격 연장, 그리고 이에 따른 Torsades de Pointes 발생 위험의 위험요소를 많이 내포하고 있으며 실제로 치명적인 부정맥인 Torsades de Pointes, 그리고 그에 따른 심정지를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

Diabetic ketoacidosis (DKA) is an acute complication related to severe hyperglycemia. While the mortality rate for DKA is low with appropriate therapy, several complications may lead to deterioration of the clinical course. Here, we report a case of a 23-year-old patient with DKA who suffered from a rare but hemodynamically unstable cardiac arrhythmia, polymorphic ventricular tachycardia with prolonged QT interval, or Torsades de Pointes. During the recovery phase of DKA, three episodes of Torsades de Pointes suddenly occurred, and were recovered by immediate defibrillation. The patient did not have structural heart disease or a genetic predisposition. To the best of our knowledge, this is the first report of an adult with DKA complicated with QT prolongation related to Torsades de Points after correction of ketosis. To manage DKA, more attention may be needed on changes in the QT interval as well as risk factors for Torsades de Points. (Korean J Med 2021;96:432-437)

신동맥의 섬유근이형성증은 비죽상경화성, 비염증성 혈관 질환으로 혈관의 협착, 동맥류, 박리, 폐색이 발생할 수 있다. 저저들은 임신 전 기저 질환이 없는 40세 임산부가 제왕절개술 후 2병일째 섬유근이형성증에 의한 신동맥 동맥류의 파열이 발생한 드문 증례를 발견하여 보고하고자 한다. 환자는 갑자기 발생한 복통으로 병원에 내원하여 시행한 복부 전산화단층촬영에서 우측 신동맥의 동맥류와 인접부위 혈관의 파열을 확인하였고, 신속한 신동맥조영술을 통한 색전술을 시행하였다. 신동맥색전술 후 일시적으로 지속성신 대체술을 시행하였고 신기능은 완전히 호전되었다.

Fibromuscular dysplasia (FMD) of the renal artery is a non-atherosclerotic, non-inflammatory vascular disease that causes stenosis, aneurysm, dissection, and occlusion of the vessel. We report a rare case of a postpartum FMD patient who presented with spontaneous acute perirenal hematoma due to renal artery aneurysm rupture after cesarean section. The 40-year-old patient presented with sudden onset of abdominal pain 2 days after an elective cesarean section performed at full gestational term. A computed tomography scan of the abdomen revealed perirenal hematomas with signs of FMD in both renal arteries. The bleeding was successfully controlled by transcatheter arterial embolization. Short-term continuous renal replacement therapy was performed until her renal function recovered. FMD of the renal artery is rare in pregnant patients. Additionally, aneurysm rupture can be life threatening and requires immediate medical attention and prompt management. (Korean J Med 2021;96:438-442)