Siriraj Medical Journal

69-72

Authors: Angsu Chartrungsan, M.D., Pansak Laksanabunsong, M.D., Akarin Nimmannit, M.D.**, Bundarika Suwanawiboon, M.D.***, Naravat Poungvarin, M.D.****, Wanchai Wongkornrat, M.D.*, Kriangkrai Tantiwongkosri, M.D., Worawong Slisatkorn, M.D., Pranya Sakiyalak, M.D., Punnarerk Thongcharoen, M.D., Thaworn Subtaweesin, M.D., Somchai Sriyoschati, M.D., Teeravit Phanchaipetch, M.D.

Objective: The ACCP guideline 2008 recommended cessation of warfarin ve days before surgery. However, based on the observation of the clinical practice at Siriraj Hospital, we suggested a shorter period of three days before surgery. Prior studies have shown multiple factors had effected warfarin dosage, but few studies have shown factors that in uenced normalization of prothrombin time after discontinuation of warfarin. Previous studies have shown the genetics factors, vitamin K epoxide reductase (VKORC1) and cytochrome P450 2C9 (CYP2C9) enzyme conjointly determine the warfarin maintenance dose. We wanted to nd out the proper timing of warfarin cessation before surgery and relationhip to genetic factors. Methods: Sixty-eight patients on warfarin were randomized to stop warfarin for three or ve days. Blood samples were acquired at three or ve days after interruption of warfarin in each group and assayed for INR, VKORC1 and CYP2C9. We started bridging therapy when INR was less than 2.0 and accepted an INR value of 1.5 or less on the day of surgery. Results: A total of 68 patients were enrolled in the study. Thirty-three patients (48.5%) were male. The mean age was 50.8 ± 6.6 years (range 16-88 years). The mean BMI was 22.5 ± 3.6 kg. All patients had mechanical heart valve replacement, and 22 (32.4%) patients had AF. The mean cumulative weekly dose of warfarin was 27 ± 11.3 mg and baseline INR was 2.4 ± 0.3. Thirty (88.2%) patients in the three days group had INR ≤ 1.5 and thirty-three (97.3%) patients in the ve days group had INR ≤ 1.5. There was no signi cant difference between interruption of warfarin for three and ve days (p =0.16). Female sex, BMI and weekly warfarin dosage were associated to the longer cessation of warfarin. Only weekly warfarin dosage was a signi cant factor after multivariate analysis. From 68 patients, CYP2C9 *1/*1 was found in 93% and CYP2C9 *1/*3 was found in 7%. Neither mutant CYP2C9*2 allele nor individuals homozygous for CYP2C9*3 were observed. Regarding VKORC1, haplotype AB was found in 32% and haplotype AA was found in 63%. Haplotype BB (wild type) was found in 4%. Five patients who had INR > 1.5 after interruption of warfarin had VKORC1 haplotype AA, four patients had CYP2C9*1/*1 and one patient had CYP2C9 *1/*3. Neither VKORC1 nor CYP2C9 was related to normalization of INR (p=0.10, p=0.17). Conclusion: Temporary interruption of the warfarin therapy between three days and ve days with bridging therapy before surgery is not signi cantly different in the Thai population. This study recommends discontinuing warfarin three days before surgery. The proper timing of interruption for warfarin does not only depend on the half-life of warfarin but also depends on age, co morbidity, sex, BMI, lower maintenance warfarin dose, and concomitant drugs. If patients have cardiac or liver disease, they may spend longer time to discontinue warfarin before surgery.Warfarin, interruption, surgery, anticoagulant, cessation

77-80

Authors: Tanita Thaweethamcharoen, Ph.D.*, Prapaporn Noparatayaporn, B.Sc.Pharm., Cherdchai Nopmaneejumruslers, M.D., Thitinan Bunrod, B.Sc.Pharm.*

Objective: To study drug expenditure and the pattern of Non-Essential drug (NED) use after the restriction policy at a large University Hospital in Thailand. Methods: The computerized data of the large University Hospital in Thailand was analyzed using a ‘I control chart’ with a statistically process-controlled method for the three highest oral drug expenditure groups of the hospital which included statins, proton pump inhibitor (PPIs), and non steroidal anti-in ammatory drugs (NSAIDs). The data of prior periods were collected before (December 2009-November 2010) and after (January 2011-August 2012) the implementation of the restricted policy of NED reimbursement was launched in December 2010. Results: Both statins and PPIs expenditure were decreased more than 30% while NSAIDs was decreased about 25% after implementation of the policy. Drug expenditure cost was decreased about 177 million Baht per year in the three groups. The patterns of drug usage were changed from NED to Essential drug (ED) about 36%, 26% and 7% in statins, PPIs and NSAIDs groups, respectively. Conclusion: The restriction of the NED prescribed policy was able to reduce the drug expenditure of the large university hospital. However the sustainable cost saving must be followed for the long term period.

85-87

Authors: Alok Saxena, M.Sc., Sachin Soni, M.S., Tuhin Ghulyani, MS., Amal Rani Das, MS.

Variations are important ndings for anatomists, radiologists and surgeons. Variations may be either skeletal or neurovascular. It may simulate the normal/abnormal (malignant) structures and misguide the radiologists and surgeons during diagnostic and surgical procedures. Hence, it becomes essential to disseminate the knowledge of variations. Keeping this in mind, we report a case of a third head of gastrocnemius in a male cadaver. This muscle was observed in the right popliteal fossa, arising from lateral condyle of femur and merging with two heads of gastrocnemius.

31-35

Authors: Lalida Tuntipumiamorn, M.Sc., Piyanan Liammookda, M.Sc., Sutee Dechawongsuwan, M.Sc., Satjah Chaikreng, B.Sc., Porntip Iampongpaiboon, M.Sc., Chumpot Kakanaporn, M.Sc.

Objective: Setup accuracy of our head and neck intensity-modulated radiation therapy (IMRT) patients based on the non- extended standard thermoplastic masks was examined using a Varian onboard imaging system. Methods: Retrospective analysis of thirty head and neck IMRT patients treated during April 2009-July 2010 was performed. All two-dimensional kilovoltage (2DkV) and cone-beam computed tomography (CBCT) images were acquired weekly during the same session and reviewed by oncologists using an of ine review 8.6 program on an Eclipse treatment planning system. Couch shifts predicted by software between 2DkV and CBCT images were recorded. The planning target volume (PTV) margin using VanHerk’s margin formula was calculated. Results: Four-hundred and forty-four images of 2DkV and CBCT alignment were analyzed. Positioning errors within ± 3 mm. were shown in 84.07% of 2DkV radiographs and 85.84% of CBCT images. Average displacement found in antero- posterior (AP), cranio-cuadal (CC) and left-right (LR) axes , were 0.3±2.0 mm , 0±1.7 mm, 0.5±1.5 mm for the 2DkV, and 0.3±2.3, 0.7±2.1, 0.4±2.1 mm for the CBCT data set, respectively. Systematic and random variations from both methods which were seen in the range of 0.5-1.8 mm. PTV margins determined from 2DkV pair images, in AP ,CC and LR directions were presented at 4.60, 3.80 and 2.41 mm. when compared to 5.4, 4.32 and 4.35 mm from CBCT, respectively. Adaptive treatment planning on six patients were undertaken as well owing to the great bene t of CBCT to detect the patient’s contour changes ,which can be seen in the range of 1.20-3.12 cm. Conclusion: Based on our immobilization masks and laser-based positioning, the majority of treatment setups were accurate within our acceptable criteria. Both 2DkV and CBCT were shown to be effective methods to reduce the residual setup error. The results from this study will be used as a baseline for further improving the setup accuracy for head and neck IMRT patients at our institution.

41-46

Authors: Kattiya Manomayangkul, M.D., Arunotai Siriussawakul, M.D., Khemchat Wangtawesap, M.D., Onuma Chaiwat, M.D., Tipa Chakorn, M.D., Sudta Parakkamodom, RN, Panisara Saengsung, RN, Thanawin Chawaruechai, RN, Chulaluk Komoltri, Dr PH.

Objective: To assess the quality of nurses’ basic life support (BLS) and to determine pitfalls in BLS in relation to ward characteristics. Setting: A 2,400-bed university hospital in Thailand. Methods: A 1-year retrospective simulated audit for 2009 to assess nurses’ BLS performance at each step. Each observer as- sessed the subjects’ performance by using a scoring sheet and noting the objective manikin data related to chest compression. Results: A total of 57 wards from intensive care units, critical wards, procedural units, general wards or outpatient units were audited. Only 24 out of 57 (42.1%) did airway maneuvers correctly, while only 2 out of 57 (3.5%) could rescue breathing with chest movement. For the circulation maneuvers, carotid pulse check, hand position, the depth and the rate of cardiac compression were mostly performed incorrectly. Exactly 14.0% of subjects did not palpate the carotid pulse, and 52.6% palpated it incorrectly. Thirty-three nurses (57.9%) located and placed their hands on the wrong position. Forty-one nurses (71.9%) did not achieve the requisite chest compression depth, while thirty-one nurses (54.4%) did not achieve the target chest compression rate. The overall BLS performance of nurses in the High Risk Zone was better than that of nurses in the Low Risk Zone, except in the case of the airway sector. Conclusion: The CPR audit evaluated the resuscitation performance during simulated cardiac arrest in the service setting, and compared wards nurses in 2 categories related to the risk of cardiac arrest. Improvement in the organisation of training and the systematic approach to CPR should be adopted.

51-54

Authors: Samut Chongvisal, M.D., Suchitra Prasansuk, M.D., Siriporn Limviriyakul, M.D., Kanthong Thongyai, M.D., Sarun Prakairungthong, M.D., Suvajana Atipas, M.D.

Deafness and hearing impairment are globally increasing. The Otological Center, Bangkok Unit, Department of Otorhinolaryngology, Siriraj Hospital is the rst World Health Organization collaborating center in terms of hearing prevention since1985. A school survey in the southern part of Thailand was conducted in 1990 for a prevalence, strengthening network, early detection and management at different levels. Our center performed a school survey at the same area to nd out the prevalence and ear pathology of hearing impairment. It was found that the prevalence of hearing impairment decreased in all severities, when compared to the prevalence found in the survey in 1990. The most common cause of ear pathology was earwax impaction.

58-68

Authors: Michiaki Takahashi, M.D., Ph.D.

No abstract available.

1-5

Authors: Tumtip Sangruchi, M.D., Panitta Sithinamsuwan, M.D., Jane Manonukul, M.D., Suteekanit Hahtapornsawan, M.D., Nattawut Sermsathanasawadi, M.D., Methee Chayakulkeeree, M.D., Theerapong Krajaejun, M.D., Ankana Chaiprasert, Dr.rer.nat, Wanchai Wanachiwanawin, M.D.

Objective: Arterial pythiosis, caused by Pythium insidiosum, is a life threatening condition. The lesions usually involve main arteries of the lower extremities, which extend to the abdominal aorta. Early amputation is required to save patient’s life. The adequacy of amputation needs to ensure that the resection margins are devoid of the organisms. The aim of this study is to suggest the level that should be devoid of organisms for surgical amputation. Methods: We studied amputated limbs of patients diagnosed as arterial pythiosis. The major arteries of the limbs were dis- sected, then serial cross cut at 0.3-0.5 cm intervals, and consecutively submitted from proximal to distal segments for routine tissue processing and staining. Segments of non-in amed vessels continuing above or below the level of arterial occlusion were identi ed. To demonstrate fungal-like hyphae, all corresponding blocks of non-in amed arteries were stained with Grocott’s methenamine silver staining (GMS) andthoroughly examined under a microscope. Results: From June 2010 to June 2011, there were 4 cases of arterial pythiosis. Chronic arteritis obliterans, acute necrotizing arteritis with thrombosis, or ruptured aneurysm was demonstrated from distal to proximal segments without skip lesions. At the level of 5 cm. from the occlusion, neither arteritis nor fungal-like hyphae was identi ed. Conclusion: Based on the evidence from only 4 cases, we have proposed that at 5 cm. or more above the occlusion, the non- in amed arteries were free of P. insidiosum, while fungal hyphae might be observed in in amed soft tissue.

9-11

Authors: Jaruda Kobkitjaroen, M.D., Jintana Jaiyen, M.Sc., Siriporn Kongkriengdach, B.Sc., Sumalee Potprasart, B.Ed., Ronnachai Viriyataveekul, M.D.

The Crithidia luciliae immuno uorescence test (CLIFT) is widely used in clinical laboratories for anti-double stranded DNA (anti-dsDNA) detection. It has comparable sensitivity and speci city to the standard method, Farr assay, but employs simpler and safer techniques. A number of CLIFT kits are commercially available. We evaluated the sensitivities and speci cities of three commercial CLIFT kits, including IMTEC, Hemagen and Euroimmun. The IMTEC kit detected IgG, IgM and IgA classes, while the Hemagen and Euroimmun kits detected only the IgG class. Farr assays were performed when three kits gave discrepant results. The gold standard methods were the consensus results of all three kits together with the Farr assay. Out of one-hundred and thirty sera, 111 sera (85%) gave concordant results by all three CLIFT kits and 19 sera (15%) gave discrepant results. Sensitivities and speci cities of the IMTEC, Hemagen and Euroimmun kits were 97.4% and 94.5%, 66.7% and 100%, and 89.7% and 94.5%, respectively. The size of the IMTEC C. luciliae was smaller than those of the other two kits, leading to more dif culty in slide reading. Factors affecting the kit’s performance may include substrate preparation and immunoglobulin class detection.

16-20

Authors: Jantima Roongruangchai, D.D.S., Ph.D., Sataporn Menbangphung, M.S., Kasem Kuedpuch, B.Sc., Nachaya Amonmettajit, B.Sc., Pae Pochanasomboon, B.Sc., Kosol Roongruangchai, M.S., M.D.

Background: Esophageal atresia (EA) or stenosis is well known among the congenital abnormalities of the esophagus which may result from the failure or incomplete recanalization after solid stage during the 8th week of human development or deviation of the tracheo-esophageal septum. The occlusion and recanalization theory of gut development cannot explain some types of esophageal atresia. Objective: To study the serial section of continuous stages of esophageal development of chick embryos from related human Carnegie stages 14-23, observe histologically whether there are occlusion and recanalization processes, at which stages and to calculate the mitotic and apoptotic indices of the epithelial lining of the esophageal lumen as well as measuring the lumen areas of each stage of esophageal development. Methods: The fertilized Leghorn hen eggs (Gallus domesticus) were incubated at different time intervals to gain ve em- bryos for each developing stage 14-23. They were processed histologically into serial sections after the total bodies were photographed. The serial sections were observed at the esophageal area by one skipped ve sections technique. The length and lumen area were measured, total epithelial cell count, mitotic and apoptotic cell counts were performed and the mitotic and apoptotic indices were calculated. Results: The lengths of the esophagus increased with advanced age from 126.80 ± 3.03 μm at stages 14 to 7, 234.80 ± 396.62 μm at stage 23. The lumen areas decreased from stages 14-16 and increased from stages 17-23. There was no evidence of occlusion at any stage. At the stages of increasing the lumen area there was also no evidence of vacuole formation. The mitotic indices decreased from stages 15-20 and were constant from stage 21-23, which showed no correlation with the lumen area. The apoptotic index was highest at stage 16 which also showed no correlation with the process of recanalization. Conclusion: By studying in the continuous stages of esophageal development, we could not demonstrate histologically the occuluded esophageal lumens, or vacuolation of the lumens at any stage. In the same way, the mitotic and apoptotic indices show no correlation with the lumen area. These results lead to the conclusion that processes of occlusion and recanalization never occur in the normal esophageal development.

24-29

Authors: Chaicharoen Tantanate, M.D.

The bleeding time is one of the oldest tests for primary hemostasis which is still performed nowadays.This test evaluates mainly the primary hemostatic function. Some preanalytical variables including patients’ physiology and hema- tological status may impact test results. Various protocols of bleeding time are performed. Each method has pros and cons, although the template bleeding time is currently preferred over other methods because it is well-standardized. Interpretation of the results according to a well-established reference range is important. At the moment, indications of bleeding time are very limited due to its poor sensitivity and reproducibility. More sensitive and speci c assays have been developed for the diagnosis of speci c conditions. However bleeding time is still useful in uremic patients. A cautionary note - this test should not be used as a screening test for prediction of bleeding preoperatively.

187-190

Authors: Wanchai Wongkornrat, M.D., Somchai Sriyoscharti, M.D., Pansak Laksanabunsong, M.D., Teeravit Phanchaipetch, M.D.,Thaworn Subtaweesin, M.D., Punnarerk Thongchareon, M.D., Pranya Sakiyalak, M.D., Worawong Slisatkorn, M.D.,Nisarat Opartkiattikul, M.D.

Background: Aspirin used after coronary artery bypass graft surgery (CABG) improved patient survival and reduced graft thrombosis. However, individual variations in the antiplatelet effect of aspirin have been reported among CABG patients. Objective: To compare the intensity of platelet aggregation between patients receiving low and high aspirin dosage in post CABG patients. Methods: We prospectively studied the effect of aspirin dosage on platelet aggregation in 100 CABG patients. Oral aspirin was discontinued prior to CABG and re-started within 12 hours after CABG. Blood samples were collected and transferred to a laboratory prior to surgery then again on postoperative days two and eight for platelet aggregation test and platelet count within three hours after venipuncture. Results: One hundred patients (sixty five male and thirty five female patients) post coronary artery bypass graft (CABG) were evaluated for eligibility to enter the trial. The percentage of platelet aggregation was compared between low dose (<100 mg/ day), and high dose (>100 mg/day) aspirin, at postoperative CABG days 2 and 8, which showed no significant difference for the platelet aggregation (p = 0.161 post CABG day 2 and p = 0.098 post CABG day 8). Conclusion: Low dosage aspirin should be used in post CABG patients because the intensity of platelet aggregation between patients post CABG receiving low and high aspirin dosage were not different, while the prophylactic effect of the low aspirin dosage in reducing the risk of cardiovascular events proved equally as effective as the high aspirin dosage.

196-199

Authors: Khemchat Wangtawesap, M.D., Arunotai Siriussawakul, M.D. Onuma Chaiwat, M.D., Tipa Chakorn, M.D.,Rapeepan Nuntabut, M.D., Daranee Kusakunniran, M.D., Sudta Parakkamodom, RN, Panisara Saengsung, RN,Thanawin Chawaruechai, RN, Wasinee Methapraphamorn, RN, Chulaluk Komoltri, DrPH (Biostatistics)

Objective: To survey the times to critical actions (defibrillator and doctor presence, initiation of chest compression) of inhospital simulated cardiopulmonary resuscitation (CPR). Methods: A 1-year retrospective simulated audit 2009 in a 2,400-bed university hospital in Thailand. Results: A total of 57 adult wards (around a third of all wards in the hospital), including intensive care units, critical wards, procedural units, general wards and out-patient units were audited. Overall, the median time of initiation of chest compression and defibrillator presence among CPR teams were 1.27 (0.35-7.19) and 1.16 (0.00-26.00) minutes, respectively. The median time of the first doctor presence was 3.45 (0.00-15.15) minutes. However, there were significant differences in time to defibrillator and doctor presence among wards. The longer time of these critical managements were recorded in non-monitored areas (general wards and out-patient units) (p = 0.004 and 0.007, respectively). Conclusion: In our CPR simulated survey, delayed initiation of critical managements commonly occurred in non-monitored areas. Better management should be concerned for favorable outcomes.

205-206

Authors: Adune Ratanawichitrasin, M.D., Somsri Ratanawichitrasin, M.D.

No abstract available.

210-214

Authors: Ananya Pongpaibul, M.D.

No abstract available.

143-146

Authors: Saifon Chawanpaiboon, M.D., Sujin Kanokpongsakdi, M.D.

Objective: To determine the preterm birth rate, neonatal birth weight and causes of early neonatal death at Siriraj Hospital over a 9-year period (2002-2010). Methods: The medical records of preterm birth, threatened preterm labor and neonatal birth weight at Siriraj Hospital from 2002 to 2010 were retrospectively collected and reviewed. The data was analyzed by SPSS version 13. Results: During a 9-year period, 2002-2010, the birth rate decreased steadily from 2002 to 2006, but increased suddenly from 2007 to 2010. The rate of preterm birth was increased steadily from 2004 to 2010 (9.44%-13.70%). The rate of threatened preterm labor was constantly between 6.0 and 8.9%. Among preterm births, low birth weight infants were mostly found except in the year 2003. Early neonatal death was mostly caused from fetal abnormality. The trend of neonatal death from prematurity had continuously declined and there was no early neonatal death from 2008 to 2010. Conclusion: Regarding this 9-year review, the preterm birth rate increased from 2007 to 2010 while premature babies mostly survived.

151-156

Authors: Chaicharoen Tantanate, M.D., Metinee Teyateeti, M.D., Panutsaya Tientadakul, M.D.

Background: Plasma interference is a problem for coagulation analyzers using a photo-optical detection method. Sysmex® CS-2100i is a fully-automated coagulation analyzer which has been developed to reduce this problem. Objective: To evaluate the influence of interferences on prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen analyzed by Sysmex® CS-2100i. The performance of this analyzer was also assessed in this study. Methods: Pooled plasma samples spiked with interfering substances including hemoglobin, bilirubin and lipid were used in the interference study. Real patients’ samples with these interferences were also tested. Control materials and pooled samples were used for precision, comparison, and carryover studies. Results: The PT, APTT, and fibrinogen could be analyzed in both plasma samples with interference added and real abnormal patients’ plasma samples. The deviation of PT, APTT, and fibrinogen levels was not obvious, except for an upward trend of fibrinogen level with increased hemoglobin. The highest % CV of PT, APTT, and fibrinogen were 1.24, 3.18, and 4.31, respectively for within-run and 2.32, 2.11, and 6.06, respectively for between-run precision analysis. The correlation coefficients of PT, APTT, and fibrinogen between Sysmex® CS-2100i and Sysmex® CA-1500 were 0.99, 0.99, and 0.98 with intra-class correlation coefficients of 0.99, 0.99, and 0.98 respectively. No significant carryover of specimen was observed. Conclusion: Sysmex® CS-2100i could analyze both samples with artificial interfering substance added and real abnormal patients’ samples. This machine also had an acceptable performance by our evaluation.

163-167

Authors: Pantip Sangprasert, RN, MNS, NP, APN

Objective: This action research used a one group pre-post test design in 75 samples and used both quantitative and qualitative methods. The study was designed to develop knowledge and basic skill practice in a hypertension program among 240 healthcare volunteers obtained as samples randomly chosen from four communities. Methods: The instrumentation employed comprised of the hypertension knowledge questionnaires, observational guide form and group discussion. All these aspects of knowledge were good quality for all volunteers in terms of discrimination = 0.48 ± 0.18, difficulty =.0.72 ± 0.49 and reliability Kuder-Richarson 20 = 0.74 with split-half = 0.81. Results: Following participation in the program, the quantitative data were the knowledge of the volunteers was increased with statistical significance (p<.001) and which was positively correlated with the level of education, but was negatively correlated with age (r = 0.224, p<.01 and r = -0.289 respectively). The qualitative data were peopleัs problems, needs and preferences for eating foods high in sodium and cholesterol, forgetting or refusing to take medication, lack of awareness about the severity of the disease and no motivation to exercise especially for elderly patients. Conclusion: This program should be useful for other healthcare volunteers in monitoring, supervising and supporting the teamwork in collaboration with community network development.

171-173

Authors: Chumpol Anamnart, M.D., Niphon Poungvarin, M.D., FRCP, FRI.

Chronic migraine (CM) is an important cause of chronic daily headache (CDH), a common severe headache syndrome. Patients with CM are significantly disabled from employment and overuse pain relieving medications. CM is a difficult condition to treat. Overuse of abortive medications and limited benefit from oral preventive medications are an important problem in managing this condition. Recent randomized controlled trials evaluating the efficacy of botulinum toxin A (BoNT-A) have confirmed its efficacy for CM prophylaxis. BoNT-A is a safe drug with no systemic reactions in clinical trials for headache.

177-184

Authors: Teerin Liewluck, M.D., Tumptip Sangruchi, M.D.

Sporadic inclusion body myositis (SIBM) is the most common idiopathic inflammatory myopathy in Caucasians over the age of 50 years. The prevalence of SIBM in the Asian population was initially thought to be very low, although the recent study showed that the prevalence of SIBM in Japan is in fact similar to the prevalence in Australia and the USA. SIBM is a refractory myositis with associated myodegenerative features mimicking the neuropathology of Alzheimer’s disease. The diagnosis of definite SIBM requires the typical clinical features and the presence of an autoaggressive inflammatory reaction, rimmed vacuoles, and congophilic deposits or tubulofilamentous inclusions. About one-fourth of patients with the typical clinical features of SIBM did not fulfill the pathological criteria of the definite SIBM. These canonical biopsy features may be absent in the early stage of the disease. Here we review the typical findings and the diagnostic pitfalls of the muscle biopsy in SIBM.