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BACKGROUND: Evaluating COVID-19 vaccine effectiveness (VE) domestically is crucial for assessing and determining national vaccination policy. This study aimed to evaluate VE of mRNA COVID-19 vaccines in Japan. METHODS: We conducted a multicenter test-negative case-control study. The study comprised individuals aged ≥16 visiting medical facilities with COVID-19-related signs or symptoms from 1 January to 26 June 2022, when Omicron BA.1 and BA.2 were dominant nationwide. We evaluated VE of primary and booster vaccination against symptomatic SARS-CoV-2 infections and relative VE of booster compared with primary. RESULTS: We enrolled 7,931 episodes, including 3,055 test positive. The median age was 39, 48.0% were male, and 20.5% had underlying medical conditions. In individuals aged 16 to 64, VE of primary vaccination within 90 days was 35.6% (95% CI, 19.0-48.8%). After booster, VE increased to 68.7% (60.6-75.1%). In individuals aged ≥65, VE of primary and booster was 31.2% (-44.0-67.1%) and 76.5% (46.7-89.7%), respectively. Relative VE of booster compared with primary vaccination was 52.9% (41.0-62.5%) in individuals aged 16 to 64 and 65.9% (35.7-81.9%) in individuals aged ≥65. CONCLUSIONS: During BA.1 and BA.2 epidemic in Japan, mRNA COVID-19 primary vaccination provided modest protection. Booster vaccination was necessary to protect against symptomatic infections.
Subject(s)
COVID-19 , SARS-CoV-2 , Male , Humans , Female , SARS-CoV-2/genetics , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , Japan/epidemiology , Case-Control Studies , Vaccine Efficacy , RNA, MessengerABSTRACT
An 83-year-old Japanese man with Alzheimer's disease was admitted to our hospital for treatment of hyponatremia resulting from water intoxication. During hospitalization, the patient developed focal impaired awareness seizures, focal to bilateral tonic-clonic seizures, and subsequent status epilepticus. Electroencephalogram during focal impaired awareness seizures showed rhythmic 5-9 Hz theta activity in the right frontotemporal region. Electroencephalogram during focal to bilateral tonic-clonic seizures showed bilateral polyspikes. Electroencephalogram during an interseizure period revealed sharp waves in the right frontal region. Continuous intravenous administration of midazolam was the only effective treatment for status epilepticus. The patient died of aspiration pneumonia on day 58. Hyponatremia-associated status epilepticus is rare; in the present case, multifocal epileptogenicity resulting from Alzheimer's disease and hyponatremia-associated elevation of glutamate levels in the synaptic cleft may have contributed to the onset of focal to bilateral tonic-clonic seizures with subsequent status epilepticus.
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BACKGROUND: Difficulty with oral feeding, the most commonly observed complication of Alzheimer disease (AD) in its final stages, occurs in 86% of AD patients and may prevent achievement of oral feeding after aspiration pneumonia. However, no reliable indicators of discontinuance of oral feeding have yet been identified. We therefore aimed to identify predictors of discontinuance of oral feeding in postaspiration pneumonia patients with AD. MATERIALS AND METHODS: Relevant clinical and laboratory data of 60 patients with AD admitted to our hospital in Japan for aspiration pneumonia were retrospectively compared between oral feeding and discontinuance groups. RESULTS: The study groups differed in interval since diagnosis of AD, CURB-65 score, pneumonia severity index score, and proportion of patients who died (higher in the discontinuance group) and body mass index (BMI), Mini Mental State Examination (MMSE) score, and functional independence measure score (lower in the discontinuance group). According to multivariate logistic regression analysis of all identified independent variables, only CURB-65 and MMSE scores and BMI are significant predictors of discontinuance of oral feeding after aspiration pneumonia in patients with advanced AD. CONCLUSIONS: In patients with advanced AD, discontinuance of oral feeding after aspiration pneumonia may be predicted by CURB-65 and MMSE scores and BMI.
Subject(s)
Alzheimer Disease/complications , Body Mass Index , Mental Status and Dementia Tests/statistics & numerical data , Pneumonia, Aspiration/complications , Aged, 80 and over , Female , Hospitalization/statistics & numerical data , Humans , Japan , Male , Retrospective Studies , Risk FactorsABSTRACT
BACKGROUND: Infective endocarditis due to Escherichia coli is a rare disease but is increasing in frequency, especially among older women. In addition, its mortality rate is higher than that of endocarditis due to the HACEK-group gram-negative bacteria (Haemophilus spp., Aggregatibacter spp., Cardiobacterium hominis, Eikenella corrodens, and Kingela spp.). CASE PRESENTATION: A 58-year-old Japanese woman with a history of alcohol abuse was admitted to our hospital because of a fever. She was diagnosed with infective endocarditis due to E. coli based on repeated blood cultures and transthoracic echocardiography, which revealed vegetations attached to the anterior leaflet and chordae tendineae of the mitral valve. Despite administration of sulbactam/ampicillin and gentamycin, she developed purulent spondylitis during hospitalization and required treatment with meropenem administration for 6 weeks, leading to resolution of the endocarditis. She took oral levofloxacin for 2 months, and the spondylitis was completely cured 7 months after discharge. CONCLUSION: Escherichia coli affects native valves without degenerative valvulopathy rather than prosthetic valves, especially in patients with risk factors such as an immunosuppressive status, excessive alcohol consumption, or treatment with hemodialysis. Peripheral embolization, congestive heart failure, and valve-ring abscesses are major complications of E. coli endocarditis; notably, infective myocarditis can also occur. The mortality and surgical intervention rates are 21% and 42%, respectively. Physicians should be cognizant of the necessity of surgical intervention when E. coli endocarditis is resistant to antibiotic therapy.
Subject(s)
Endocarditis, Bacterial/microbiology , Escherichia coli Infections/microbiology , Escherichia coli/isolation & purification , Mitral Valve/microbiology , Alcoholism/complications , Anti-Bacterial Agents/therapeutic use , Echocardiography , Endocarditis, Bacterial/diagnosis , Endocarditis, Bacterial/drug therapy , Escherichia coli/drug effects , Escherichia coli Infections/diagnosis , Escherichia coli Infections/drug therapy , Female , Humans , Middle Aged , Mitral Valve/diagnostic imaging , Remission Induction , Risk Factors , Spondylitis/microbiology , Suppuration/microbiology , Time Factors , Treatment OutcomeABSTRACT
A 94 year-old Japanese woman with renal dysfunction was admitted to our hospital for congestive heart failure caused by atrial fibrillation with rapid ventricular response. Considering the risk of stroke, warfarin was commenced. However, she developed shock following brachial and retroperitoneal hemorrhage 4 days after starting warfarin despite not being over-anticoagulated. She recovered after receiving blood transfusion and intravenous vitamin K2. Bleeding during warfarin administration occurs more frequently in older individuals with lower glomerular filtration rates, especially within the first 30 days of warfarin treatment. Physicians should therefore check for unexpected bleeding after commencing warfarin and be prepared to reverse anticoagulation.
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BACKGROUND: Spontaneous isolated dissection of the superior mesenteric artery (SMA) can lead to bowel ischemia, aneurysm rupture, or even death. Studies have suggested that mechanical or hemodynamic stress on the vascular wall of the SMA may be a contributor, but its pathogenesis is unclear. CASE PRESENTATION: A 57-year-old Japanese man with a history of untreated hypertension and hyperuricemia was admitted to our hospital with the sudden onset of severe epigastric pain. Laboratory findings showed elevated white blood cell count and C-reactive protein, and contrast-enhanced computed tomography (CT) of the abdomen demonstrated arterial dissection with luminal stenosis and aneurysm formation at the distal portion of the SMA after the branching of the jejunal artery, and intravenous nicardipine was administered. The patient's epigastric pain resolved spontaneously but recurred on day 6 of his hospital stay. Contrast-enhanced abdominal CT revealed an enlarged aneurysm with wall thinning. Because of the risk of aneurysm rupture, the decision was made to perform aneurysmectomy and bowel resection on day 6. Histologic examinations revealed two separate dissecting lesions: one latent and the other resulting in aneurysm formation. Both lesions showed characteristics of segmental arterial mediolysis (SAM) with lack of arterial media, absence of internal and external elastic laminae and intimal proliferation. CONCLUSIONS: Histologic findings in the present case suggest that mechanical or hemodynamic stress on the vascular wall and SAM-related vascular vulnerability may concomitantly contribute to the onset of isolated SMA dissection.
Subject(s)
Aneurysm, Ruptured/diagnostic imaging , Mesenteric Artery, Superior/diagnostic imaging , Aneurysm, Ruptured/pathology , Aneurysm, Ruptured/surgery , Contrast Media , Humans , Male , Mesenteric Artery, Superior/pathology , Mesenteric Artery, Superior/surgery , Middle Aged , Tomography, X-Ray ComputedABSTRACT
Acute suppurative thyroiditis is a serious disease; therefore, its diagnosis in the acute phase is important. Fine needle aspiration biopsy of the thyroid gland plays a pivotal role in the diagnosis of acute suppurative thyroiditis. Appropriate culture technique and optimal imaging modalities are also important for its diagnosis.
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BACKGROUND: Pneumatosis intestinalis (PI) is a rare condition characterized by the presence of gas within the gastrointestinal tract wall. Most cases of PI have a benign clinical course, although some have serious outcomes. Mechanical stress on or bacterial infection of the gastrointestinal tract wall may be responsible for the onset of PI, but the detailed mechanism of PI pathogenesis is still unclear. Here, we describe two Japanese patients presenting with benign PI. CASE PRESENTATION: Case 1, a 37-year-old previously healthy male patient, had a 1-week history of abdominal pain, and case 2, a 78-year-old female diabetic patient, had a 2-week history of voglibose treatment and abdominal pain. Intramural gas was mainly distributed in the colon in case 1 and in the small intestine in case 2. Interestingly, neither patient showed obvious inflammatory signs upon admission and recovered spontaneously with conservative treatment, including fasting and fluid infusion without antibiotics. Voglibose treatment was terminated in case 2. Recent studies have shown the presence of nonpathogenic bacteria, such as Clostridium spp., in PI lesions, which usually play an important role in modulating the tolerance of the gastrointestinal immune responses. The benign clinical course and spontaneous resolution of PI in these patients, without specific treatment, suggests that nonpathogenic indigenous bacteria in the gastrointestinal tract participate in the pathogenesis of PI. CONCLUSION: In patients with benign PI, the absence of an inflammatory response and the spontaneous resolution of the disease without specific treatment suggest the participation of nonpathogenic indigenous bacteria of the gastrointestinal tract.
Subject(s)
Gastrointestinal Diseases/pathology , Adult , Aged , Female , Gastrointestinal Diseases/diagnostic imaging , Humans , Male , Radiography, Abdominal , Tomography, X-Ray ComputedABSTRACT
An 84-year-old Japanese man taking warfarin to prevent cerebral infarction secondary to atrial fibrillation was admitted to our hospital for evaluation of a painless right back mass. Magnetic resonance imaging (MRI) showed an oval-shaped mass in the right psoas major muscle. The mass showed high intensity on T1-, T2-, and diffusion-weighted imaging and mimicked an acute-phase hematoma. However, it showed no chronological changes typical of a hematoma, and MRI revealed enlargement of the mass 1 week after admission. Histopathological examination of a biopsy specimen revealed diffuse large B-cell lymphoma (DLBCL). Although skeletal muscle lymphoma is rare, physicians should be familiar with its MRI characteristics. In addition, determination of the lymphoma subtype has important implications for the treatment of skeletal muscle lymphoma because DLCBL may have an especially poor prognosis.
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The Streptococcus milleri group (SMG) comprises commensal mucosal bacteria. Pyogenic liver abscesses due to hematogenous SMG infection are rare but can be observed even in healthy patients. In such cases, physicians should consider the existence of primary lesions that allow penetration of the SMG.
ABSTRACT
A 78-year-old Japanese man was admitted to our hospital because of fever lasting for 4 days. His white blood cell count and C-reactive protein level were elevated and computed tomography of the chest showed bronchopneumonia in the right upper lobe of the lung. Streptococcus pyogenes was detected from sputum and blood culture samples on admission and administration of ampicillin/sulbactam was effective. Although our patient's clinical course was good, S. pyogenes pneumonia commonly shows a high rate of fatality and septicemia, and may affect a previously healthy population. Physicians should be aware of pernicious characteristics of S. pyogenes pneumonia.
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BACKGROUND: Pneumococcal pneumonia is the most common form of community-acquired pneumonia (CAP). Although a pneumococcal conjugate vaccine has contributed to a reduction in the incidence of pneumococcal pneumonia among older children and adults, no significant decrease in the incidence has been observed among persons aged ≥65 years. A low body mass index and hypoalbuminemia are common in Japanese patients with CAP, but the association of other nutritional parameters with the severity of pneumonia or length of hospital stay in patients with pneumococcal pneumonia is unclear. METHODS: Fifty-seven previously healthy inpatients who presented with pneumococcal pneumonia were divided into two groups: those aged ≥65 years (n = 36) and those aged <65 years (n = 21). Patients' characteristics (the Confusion, Urea, Respiratory rate, Blood pressure, age >65 years (CURB-65) score), the pneumonia severity index (PSI), and inflammatory and metabolic nutritional parameters were compared between the two groups. RESULTS: The older group showed significantly lower serum albumin and cholinesterase (ChE) levels. Multivariate linear regression analysis revealed that the PSI was positively correlated with age in both groups. In the younger age group, both the CURB-65 score and PSI showed significant negative correlations with the serum ChE level, and there was a significant negative correlation between the length of stay and serum total cholesterol (T-cho) level. In the older group, the fasting period, lymphocyte count, and age showed significant positive correlations with the length of stay. There was a significant negative correlation between the length of stay and serum albumin level, but no correlation with the serum ChE or T-cho levels, in the older patients. CONCLUSIONS: Our findings suggest that in patients aged <65 years, age and serum ChE and T-cho levels were associated with both the severity of pneumococcal pneumonia and length of stay. In contrast, the length of stay in older patients was associated with multiple factors that differed from those in younger patients. These differences may reflect age-related immunosenescence in older patients and a greater effect of serum ChE and T-cho levels on immunity in younger patients.
Subject(s)
Community-Acquired Infections/epidemiology , Hospital Mortality , Length of Stay/statistics & numerical data , Nutritional Status , Pneumonia, Pneumococcal/epidemiology , Adult , Age Factors , Aged , Aged, 80 and over , Cholesterol/blood , Cholinesterases/blood , Cross-Sectional Studies , Female , Humans , Linear Models , Male , Middle Aged , Multivariate Analysis , Prognosis , Retrospective Studies , Severity of Illness IndexABSTRACT
Secondary cardiac cancer most frequently originates from primary lung cancer and most commonly occurs in the pericardium. On electrocardiographic examination, patients with secondary cardiac cancer occasionally show ST segment elevation that mimics acute coronary syndrome, despite the absence of coronary artery occlusion. We herein describe a rare case of secondary cardiac cancer that presented with ST segment elevation and review the literature regarding ST segment elevation caused by secondary cardiac cancer. A 73-year-old Japanese woman was admitted to the hospital with chest pain. Electrocardiography showed abnormal ST segment elevation in the precordial and lateral leads, suggestive of ST-elevation myocardial infarction. Emergency coronary angiography showed occlusion of the distal left anterior descending coronary artery (LAD), and plain old balloon angioplasty of the LAD was performed. The ST segment elevation initially resolved after angioplasty, but recurred after 7 days. Contrast-enhanced chest computed tomography showed primary lung cancer in the left lower lobe, pericardial metastasis, and myocardial metastasis in the intraventricular septum and posterolateral wall of the left ventricle. Histopathological examination of the lung cancer was not performed. Patients with ST segment elevation due to secondary cardiac cancer may have symptoms and electrocardiographic changes mimicking anteroseptal or lateral infarction without the development of abnormal Q waves. These findings are frequently associated with posterolateral or anteroseptal invasion by primary lung cancer and may indicate a poor prognosis. In conclusion, physicians should be aware that secondary cardiac cancer may present with symptoms and ST segment elevation mimicking acute coronary syndrome, indicating a poor prognosis.
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BACKGROUND: Although statin therapy significantly reduces cardiovascular morbidity and mortality, atherosclerotic plaque progresses in some patients taking statins. This study investigated the factors associated with onset of acute coronary syndrome (ACS) early after the initiation of statin therapy. METHODS: Consecutive patients taking statins who presented with ACS (n = 64) were divided into < 1-year and > 1-year groups based on the duration of statin therapy. Patient characteristics, coronary risk factors, lesion locations, and percutaneous intervention procedures were compared between groups. RESULTS: The < 1-year group was significantly younger (57.6 ± 11.9 years vs. 76.6 ± 9.1 years, P < 0.01), had significantly higher body mass index (27.22 ± 4.20 kg/m(2) vs. 24.60 ± 4.65 kg/m(2), P < 0.05), higher proportion of males (94% vs. 70%, P < 0.05), higher proportion of current smokers (61% vs. 17%, P < 0.01), and lower proportions taking aspirin and calcium antagonists (both 17% vs. 57%, P < 0.05) than the > 1-year group. In the < 1-year group, there were significant correlations between the low-density lipoprotein cholesterol (LDL-C) and triglyceride (TG) levels (r = 0.649, P = 0.004) and between the TG and hemoglobin (Hb)A1c levels (r = 0.552, P = 0.018), but these correlations were not observed a year before admission. TG level was the only parameter associated with LDL-C and HbA1c levels. CONCLUSIONS: A linear correlation between the LDL-C and TG levels, obesity, older age, male sex, and smoking may be associated with increased risk of onset of ACS early after the initiation of statin therapy. Prospective cohort studies are needed to further explore these interactions.
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BACKGROUND: Spontaneous isolated superior mesenteric artery dissection is a rare disease that may cause bowel ischemia or aneurysm rupture and subsequent death. Thus, the establishment of a correct diagnosis in the early stage is quite important. OBJECTIVE: To describe the presentation of 3 patients diagnosed with spontaneous isolated supramesenteric artery dissection and briefly summarize the diagnostic procedure, treatment, and clinical course. CASE REPORTS: We experienced three cases of isolated mesenteric artery dissection in the past 5 years. A definitive diagnosis was obtained by abdominal spiral computed tomography in two cases and angiography in one case. All patients were provided anticoagulation therapy. CONCLUSION: One patient died of bowel ischemia, 2 were discharged within 21 days without complications, and one was able to discontinue anticoagulation therapy 12 months after discharge. The remaining patient has continued warfarin, making it difficult to determine the end point of anticoagulation.
Subject(s)
Mesenteric Artery, Superior/injuries , Vascular Diseases/diagnostic imaging , Vascular Diseases/drug therapy , Abdominal Pain/etiology , Adult , Anticoagulants/therapeutic use , Heparin/therapeutic use , Humans , Male , Mesenteric Artery, Superior/diagnostic imaging , Mesenteric Ischemia/etiology , Middle Aged , Rupture, Spontaneous/diagnostic imaging , Tomography, Spiral Computed , Vascular Diseases/complications , Warfarin/therapeutic useABSTRACT
BACKGROUND: Escherichia coli (E. coli) is the most common causative bacteria of neonatal meningitis, but hematogenous intracranial E. coli infection is rare in adults. Moreover, intracranial abscess formation owing to E. coli, including brain abscesses and subdural empyema formation, is extremely rare. We herein present a case involving a patient with a brain abscess owing to E. coli following a simple renal cyst infection. A review of the literature is also presented. CASE PRESENTATION: A 77-year-old Japanese woman with a history of polymyalgia rheumatica was admitted to our hospital because of persistent fever, right flank pain, and pyuria. Intravenous antibiotics were administered; however, her level of consciousness deteriorated 6 days after admission. Contrast-enhanced magnetic resonance imaging showed a brain abscess in the left occipital lobe and pyogenic ventriculitis. Enhanced abdominal computed tomography revealed a right renal cyst with heterogeneous content. Culture of urine, blood, and aspirated pus from the infected cyst revealed E. coli with identical antibiotic sensitivity in all sites, suggesting that the cyst infection and subsequent bacteremia might have caused the brain abscess. The patient recovered after a 6-week course of meropenem. CONCLUSION: The prognosis of patients with E. coli-associated intracranial abscess is usually poor. Advanced age and immunosuppression may be potent risk factors for intracranial abscess formation owing to the hematogenous spread of E. coli.
Subject(s)
Brain Abscess/etiology , Cysts/complications , Escherichia coli Infections/etiology , Kidney Diseases/complications , Aged , Brain Abscess/diagnostic imaging , Brain Abscess/pathology , Cysts/diagnostic imaging , Cysts/pathology , Empyema/complications , Escherichia coli Infections/microbiology , Escherichia coli Infections/pathology , Female , Humans , Kidney Diseases/diagnostic imaging , Kidney Diseases/pathology , Radionuclide ImagingABSTRACT
Patients with compression of the celiac axis by the median arcuate ligament may develop aneurysms in the pancreaticoduodenal arcades. We experienced two cases of ruptured pancreaticoduodenal artery aneurysm associated with this condition. Both patients presented with abdominal pain and shock, and abdominal contrast-enhanced computed tomography showed retroperitoneal hematoma and compression of the celiac axis by the median arcuate ligament. Both patients were successfully treated by coil embolization. Patients with celiac axis compression or stenosis may develop recurrent aneurysms unless revascularization of the celiac axis is performed. Long-term follow-up is required because aneurysms may develop after 10 years or longer.
ABSTRACT
Viral myocarditis presents with various symptoms, including fatal arrhythmia and cardiogenic shock, and may develop chronic myocarditis and dilated cardiomyopathy in some patients. We report here a case of viral myocarditis with liver dysfunction and pancreatitis. A 63-year-old man was admitted to our hospital with dyspnea. The initial investigation showed pulmonary congestion, complete atrioventricular block, left ventricular dysfunction, elevated serum troponin I, and elevated liver enzyme levels. He developed pancreatitis five days after admission. Further investigation revealed a high antibody titer against coxsackievirus A4. The patient's left ventricular dysfunction, pancreatitis, and liver dysfunction had resolved by day 14, but his troponin I levels remained high, and an endomyocardial biopsy showed T-lymphocyte infiltration of the myocardium, confirming acute myocarditis. The patient underwent radical low anterior resection five weeks after admission for advanced rectal cancer found incidentally. His serum troponin I and plasma brain natriuretic peptide levels normalized six months after admission. He has now been followed-up for two years, and his left ventricular ejection fraction is stable.This is the first report of an adult with myocarditis and pancreatitis attributed to coxsackievirus A4. Combined myocarditis and pancreatitis arising from coxsackievirus infection is rare. This patient's clinical course suggests that changes in his immune response associated with his rectal cancer contributed to the amelioration of his viral myocarditis.
Subject(s)
Coxsackievirus Infections/diagnosis , Coxsackievirus Infections/pathology , Enterovirus/isolation & purification , Hepatitis, Viral, Human/etiology , Myocarditis/etiology , Pancreatitis/etiology , Coxsackievirus Infections/virology , Enterovirus/classification , Hepatitis, Viral, Human/complications , Hepatitis, Viral, Human/pathology , Humans , Immunocompromised Host , Male , Middle Aged , Myocarditis/complications , Myocarditis/pathology , Pancreatitis/complications , Pancreatitis/pathology , Rectal Neoplasms/complications , Rectal Neoplasms/diagnosisABSTRACT
The early institution of enteral nutrition is associated with beneficial outcomes and intestinal growth in pediatric patients. However, the number, frequency, and types of unfavorable events occurring with particular formulas are undefined. We experienced unexpected complications in two cases following a change in formula. One case diagnosed with myotubular myopathy experienced highly-increased gastric residuals and watery diarrhea leading to decreased calorie intake and weight loss. The second case with campomelic dysplasia suffered liver dysfunction and fever. In both cases, symptoms developed soon after of the change in formula and improved after resumption of the previous formula. Both cases had undergone tracheostomy and artificial ventilation, and had a history of feeding the same formula for an extended period of time. In chronic care patients such as ours, a change in formula may cause unexpected adverse events; therefore, caution is warranted.
ABSTRACT
A 96-year-old woman with a 5-year history of multiple myeloma was admitted to our hospital because of increasing fatigue and fever. Bone marrow plasma cell analysis showed t(11;14), del(13q), and del(17p13). Her condition deteriorated, and she developed plasmacytosis resembling plasma cell leukemia. Chromosome analysis showed trisomy of chromosome 8 in the circulating plasma cells. The plasmacytosis resolved spontaneously without chemotherapy after about 5 weeks, and the trisomy became undetectable. The findings suggest that trisomy 8 might have contributed to the transient plasmacytosis, and that chromosome 8 carries genes associated with plasma cell proliferation, maturation, and apoptosis.