Abstract: A 42-year-old man had biochemical and somatic abnormalities compatible with pseudohypoparathyroidism type I (PsHP) and also had high plasma renin activity (PRA). After 1, 25-dihydroxyvitamin D (calcitriol) supplementation the systolic/diastolic blood pressure, assessed by 24-hour non-invasive ambulatory blood pressure monitoring, was reduced from 145/96 mmHg to 128/85 mmHg with normalization of the serum calcium level and its related hormones, as well as decreased PRA. Calcitriol supplementation successfully reduced the blood pressure in this patient with PsHP and a high PRA, suggesting that calcium-related hormones and/or the renin-angiotensin system were involved in lowering the blood pressure.(Internal Medicine 38: 31-35, 1999)

Abstract: Primary pulmonary hypertension (PPH) is a progressive disease of unknown etiology usually followed by death within 5 years after diagnosis. Although heart-lung or lung transplantation is now offered to patients with advanced PPH, adequate criteria assessing an accurate prediction of life expectancy in PPH has been difficult to establish. The aims of this study were to identify the characteristic features associated with a poor prognosis in patients with PPH, and to attempt to establish an individual prognostic index that predicts with great accuracy survival or death of PPH after one year, thereby helping to define criteria for patient selection for transplantation. In 1991, a retrospective nation-wide survey on PPH was conducted in Japan, and the clinical and cardiorespiratory variables of 223 PPH cases (female; 144, male; 79) in the period from 1980-1990 were obtained. The mean pulmonary arterial pressure (PPA) was 57.5+/-17.2 mm Hg (mean+/-SD), and the overall median survival time was 32.5 months since the first diagnostic catheterization. The characteristic features of 61 patients who died within one year of catheterization (Nonsurvivors group) were compared to 141 patients who survived one year or more from the time of catheterization (Survivors group). Among several clinical and cardiorespiratory variables, heart rate, PPA, right atrial pressure (PRA), stroke volume index (SI), pulmonary vascular resistance, and partial pressure of carbon dioxide (PaCO2) were significantly different between the two groups. As the independent factors, PPA, PRA, SI, and PaCO2 were selected for the multiple logistic analysis. Using a 0.7 probability cut-point to separate Nonsurvivors from Survivors, 84.6% of Nonsurvivors and Survivors could be correctly predicted from this logistic regression equation. Predictive equations like the present preliminary one can be used in the future to better assess life expectancy in patients with PPH in whom transplantation will be considered.

Abstract: Object: To examine the role of human leukocyte antigen (HLA) class II genes in the development of systemic sclerosis (SSc) as well as in the clinical and serologic expression of SSc in patients. Methods: HLA-DRB1, DRB3, DRB4, DQB1, and DPB1 alleles were determined by genotyping; and serum antinuclear antibodies were identified using indirect immunofluorescence, double immunodiffusion and immunoprecipitation. Patients: One hundred and five Japanese patients with SSc and 104 race-matched healthy controls. Results: Frequencies of DRB1 and DQB1 alleles were not different between SSc patients and healthy controls, while DPB1*0901 was marginally increased in SSc patients. In contrast, SSc-related autoantibodies were closely associated with the clinical features. HLA class II genes were detected as follows: anti-DNA topoisomerase I antibody with diffuse cutaneous involvement, pulmonary fibrosis, and DRB1*1502-DQB1*0601-DPB1*0901; anti-U1RNP antibody with overlapping features of lupus and/or myositis and DRB1*0401/*0802-DQB1*0302; and anticentromere antibody with limited cutaneous involvement and DRB1*0101-DQB1*0501-DPB1*0402. In the analysis of the association of HLA class II and the clinical features in SSc patients significant differences were obtained only for the increased frequencies of arthritis and rheumatoid factor in patients with DRB1*0405 compared to those without. Conclusion: HLA class II genes strongly influence the production of SSc-related autoantibodies rather than the development of SSc. In addition, SSc is a composite disease of distinctive subsets defined by serum autoantibodies, which have specific clinical and HLA class II associations.(Internal Medicine 38: 336-344, 1999)

Abstract: A twenty-year-old woman with anorexia nervosa (body mass index=11) suffered from severe liver dysfunction (aspartate aminotransferase 5,000 IU/l, alanine aminotransferase 3,980 IU/l, prothrombin time 32%), hypoglycemia (serum glucose 27 mg/dl), and pancreatic dysfunction (amylase 820 IU/l, lipase 558 IU/l). She fell into a depressive state with irritability, which was not improved by intravenous glucose. Despite treatment with plasmapheresis for the liver dysfunction, she subsequently developed pulmonary edema, acute renal failure, gastrointestinal bleeding, and disseminated intravascular coagulation. Hemodialysis, mechanical ventilation and drug therapy including prednisolone, prostaglandin E1, and branched-chain amino acid, improved her critical condition. In this case, malnutrition may have been the cause for the liver dysfunction and subsequent complications.

Abstract: Object To know how Japanese patients perceive their physicians without a white coat during consultations. Subjects and Methods The patients who visited a university clinic were divided into two groups: those seen by a physician in a white coat (the white-coat group) and those seen by a physician in private clothes (the private-clothes group). Questionnaires were distributed to the patients, which asked the tension and satisfaction of consultations as well as their preference for physician's attire. The answers of the white-coat group were compared with those of the privateclothes group. Results The percentage of new patients who felt tense during consultations was greater in the white-coat group (42%) than in the private-clothes group (33%). Seventy-one percent of the patients in the white-coat group preferred physicians in a white coat whereas only 39% preferred so in the private-clothes group (p<0.0001). However, the degree of patients' satisfaction for the consultation showed no statistical difference between the groups. Sixty-nine percent of the patients older than or equal to 70 years preferred a white coat while 52 percent of the patients younger than 70 years preferred so (p=0.002). Conclusion Physician's white coats did not influence the satisfaction with the consultations for most Japanese patients in a university clinic, although elderly patients as well as those seen by a physician in a white coat tended to prefer the white coat to the private clothes. Furthermore, practice without a white coat might reduce patients' tension during their first consultation.(Internal Medicine 38: 533-536, 1999)

Abstract: Objective To evaluate efficacy of low dose prednisolone maintenance in patients with primary Sjogren's syndrome. Methods An open, prospective pilot study of prednisolone for the treatment of 20 patients with primary Sjogren's syndrome was performed. Evaluations included the amount of whole saliva measured by the Saxon test, serological abnormalities and oral symptoms. Results Initial dosage of prednisolone was 15.0±1.5 (mean±SEM) mg/day. Maintenance dosage was 7.5-5.0 mg/day. Follow-up period was 26.3±3.8 months (range 3-48). The amount of whole saliva significantly increased after 1 month of prednisolone therapy and the increase continued up to 48 months by maintaining low-dose prednisolone. A mean percent increase of whole saliva from baseline ranged from +105.2±36.2% to +245.7±82.1%. Serum IgG, anti-SS-A/Ro, anti-SS-B/La antibodies and IgM rheumatoid factor levels significantly decreased throughout the study with partial decreases of IgA and IgM levels. The improvement of subjective oral symptoms was also confirmed. Conclusion Low-dose prednisolone maintenance may have a worthwhile clinical benefit in patients with primary Sjogren's syndrome that deserves further evaluation in a controlled trial.(Internal Medicine 38: 938-943, 1999)

Abstract: Objective Evaluation of the usefulness of the serial daterminations of serum alpha-L-fucosidase (AFU) activity for prediction of the development of hepatocellular carcinoma (HCC) was performed. Methods and Patients Serum AFU activity was determined monthly for 42 months in 73 patients with liver cirrhosis (LC). Results HCC was diagnosed in 27 patients by means of ultrasonography during this observation period. In 23 (85%) of the 27 patients, serum AFU activity was found to exceed 700 nmole/ml/h during the LC stage. HCC developed within a few years in 23 (82%) of 28 LC patients with AFU activity exceeding 700 nmole/ml/h, in contrast, it developed in only 4 (9%) of 45 LC patients with AFU activity below 700 nmole/ml/h. AFU activity was already elevated in 23 (85%) of 27 patients at least 6 months before the detection of HCC by ultrasonography. Conclusion It is conceivable that the development of HCC can be predicted by means of serial determinations of serum AFU activity in patients with LC.(Internal Medicine 38: 927-931, 1999)

Abstract: Objective Thiopurine S-methyltransferase (TPMT) is a cytosolic enzyme that preferentially catalyzes the S-methylation of aromatic and heterocyclic sulfhydryl compounds, including Azathioprine (AZA). It has been reported that the level of AZA toxicity is dependent on the TPMT genotypes in Caucasian individuals; we thus investigated this relationship in Japanese. Methods The TPMT genotype was determined using peripheral blood cell DNA obtained from 36 Japanese patients with rheumatic diseases who were treated with AZA, by polymerase chain reaction (PCR) technique. Duration of AZA administration, white blood cell counts before and after AZA administration, and side effects were investigated in each subject, and were compared between the patients with or without TPMT mutation. Results The TPMT allelotype was TPMT * 1/TPMT * 1 in 33 (91.7%) and TPMT * 1/TPMT * 3C in 3 (8.3%) individuals. All 3 patients (100%) with the mutant TPMT allele (TPMT * 3C) discontinued AZA treatment due to leucopenia while only 4 patients (12%) without mutant TPMT alleles showed leucopenia (p=0.0049, Fisher's exact test). However, leucopenia developed relatively late in patients with mutant TPMT. Conclusion The TPMT mutant allele, TPMT * 3C, also exists in Japanese individuals, and the bone marrow toxicity of AZA is likely stronger in patients with this mutant allele.

Abstract: We investigated the immediate effect of respiratory muscle stretch gymnastics (RMSG) and diaphragmatic breathing (DB) on the respiratory pattern in patients with chronic obstructive pulmonary disease (COPD). Sixteen patients with COPD (age, 71.3 +/- 3.9 year) were entered in the study. DB was performed for 10 minutes in supine position. For RMSG, 5 patterns were repeated 10 times each. Respiratory variables were measured in sitting position before and after both RMSG and DB, performed in random order, patient to patient, with a 20-minute washout period in-between. After RMSG, but not after DB, there was a significant overall prolongation in expiratory time. After DB, but not after RMSG, there was an overall decrease in minute ventilation, carbon dioxide output, respiratory gas exchange ratio, end tidal O2 fraction, end tidal CO2 fraction and tidal diaphragmatic volume. The results suggest that RMSG may have a beneficial effect on the respiratory pattern. On the other hand, DB may provoke post-hyperventilation hypoxemia.

Abstract: A 56-year-old woman with symptoms of chronic bowel disease presented a peculiar calcification of the mesenteric vein of the ascending to transverse colon on barium enema study. The resected colon was hard and black. Histo-pathologic examinations demonstrated fibrous change of the colon with a calcified and hyaline-deposited mesenteric vein. No cell infiltration was observed. These findings were compatible with phlebosclerosis and also with systemic sclerosis. Positive anti-centromere antibody and Raynaud's phenomenon, hallmarks of a variant systemic sclerosis, the CREST syndrome were observed. We therefore speculated that the pathogenesis of the phlebosclerosis of the colon is related to the CREST syndrome.

Abstract: Object X-linked agammaglobulinemia (XLA) is one of the most common humoral immunodeficiencies characterized from childhood by the absence of peripheral B lymphocytes, reduced levels of serum immunoglobulins and recurrent and severe bacterial infections. These characteristics are the result of Bruton's tyrosine kinase (Btk) protein deficiency in peripheral B lymphocytes. In addition to typical XLA, several atypical cases have been recognized, who exhibited mild or even no clinical symptoms, although they were definitely deficient in Btk protein (atypical XLA). In these patients peripheral B lymphocytes and serum immunoglobulins (Igs) are detectable though at a lower level than in normal people. To clarify the discrepancies between the Btk gene mutations and the phenotypes more atypical patients should be examined. In this study we evaluated the cytoplasmic Btk protein in peripheral monocytes of some hypogammaglobulinemia adults by means of flowcytometric analysis. Materials and Methods Heparinized venous blood samples were collected from some hypogammaglobulinemia adults. Mononuclear cells were separated from their blood and first reacted with a phycoerythrin-labeled CD14 monoclonal antibody (MoAb) (staining of monocyte membrane). Next, the cells were fixed and permeabilized. And then these permeabilized cells were reacted with an anti-Btk MoAb (staining of cytoplasmic Btk protein) and incubated with a FITC-conjugated goat antimouse IgGl. The double-stained cells were analyzed on a flowcytometer. Results and Conclusion By means of flowcytometric analysis we diagnosed three hypogammaglobulinemia adults as XLA, who did not show typical clinical progress of XLA. Advancements in diagnostic methods has facilitated a prompt and definite diagnosis of this disease.(Internal Medicine 38: 722-725, 1999)

Abstract: Object Toxoplasmic encephalitis (TE), primary central nervous system lymphoma (PCNSL) and progressive multifocal leukoencephalopathy (PML) are major central nervous system (CNS) diseases in patients with acquired immunodeficiency syndrome (AIDS). We assessed the diagnostic value of polymerase chain reaction (PCR) in the detection of DNAs of Toxoplasma gondii (T. gondii), Epstein-Barr virus (EBV) and JC virus (JCV) in the cerebrospinal fluid (CSF). Methods We compared the PCR results with those of pathological findings at autopsy. Patients or Materials The present study included 23 autopsies representing those in whom CSF samples were obtained before death while the patient was hospitalized or at autopsy. Results The threshold levels for PCR detection were 4 tachyzoites of T. gondii, 5-15 genomes of EBV and 10 genomes of JCV. We identified T. gondii DNA in 4 out of 5 autopsy-defined cases of TE, EBV DNA in 5 out of 5 cases with PCNSL, and JCV DNA in 2 out of 2 cases with PML. The specificity of PCR was 100% in TE, 78 % in PCNSL, and 100 % in PML. Conclusion Although the number of cases was relatively small in this study, PCR correctly identified T. gondii DNA in those cases in which PML or PCNSL was the sole clinical diagnosis. Our results indicate that PCR examination of CSF is a clinically useful tool for the diagnosis of focal brain lesions in patients with AIDS.(Internal Medicine 38: 556-562, 1999)

Abstract: Eighteen patients with active Crohn's disease were treated with one leukocytapheresis session per week for a five-week intensive therapy, decreasing to one leukocytapheresis session per month for five sessions of initial maintenance therapy. Nutritional indices, inflammatory reactions, flow cytometry profiles, and cytokine production were also assessed before and after the intensive and initial maintenance therapy. Nine of the patients (50%) attained remission at the end of the intensive therapy. The nine non-remission patients had exhibited longer periods of suffering and more severely affected sites prior to the therapy. In 14 of 18 patients (77.8%), the nutritional indices, Internal Organization of Inflammatory Bowel Disease (IOIBD) score and Crohn's Disease Activity Index (CDAI) improved from the pretherapy levels, but only the remission group (50%) showed improvement in C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). The remission group showed significantly higher pretherapy CD4 + CD45 + cell ratios and interleukin-2 (IL-2) production than the non-remission group, and significantly lower activated cells.

Abstract: We report a 15-year-old Japanese girl with severe systemic Weber-Christian disease (WCD) who presented with acute onset of high fever associated with tender subcutaneous nodules Laboratory tests showed an elevated serum concentration of lactate dehydrogenase (LDH), leukopenia, and coagulation abnormalities The anti-nuclear and anti-DNA antibodies were negative, and the serum pancreatic enzymes and alpha 1-antitrypsin levels were normal Pulse steroid therapy was not effective, and eventually cerebellar hemorrhage occurred After initiation of oral cyclosporin A (CyA) therapy, fever came down and her clinical condition improved markedly Extremely high serum concentrations of interferon-gamma (IFN-gamma) and soluble interleukin-2 receptor (sIL-2R) in this patient returned to normal with CyA therapy These findings suggest that T-cell immune responses are involved in the pathogenesis of WCD, and that CyA is effective against the disease via suppression of T-cell reactions

Abstract: A 54-year-old man with medullary thyroid carcinoma in the thyroid gland was unable to undergo total thyroidectomy because the tumor had invaded the mediastinum. Radiation therapy and chemotherapy were given. Seven years later, intractable diarrhea and abdominal pain appeared, and computed tomography demonstrated hypervascular tumors in the thyroid gland and in the liver. The tumors were successfully treated with percutaneous ethanol injection to a lesion in the thyroid gland and transcatheter arterial embolization followed by percutaneous ethanol injection to tumors in the liver. Transcatheter arterial embolization and percutaneous ethanol injection may be valuable in treating medullary thyroid carcinoma.

Abstract: A 62-year-old Japanese male developed multiple hepatic metastases two years after resection of pheochromocytoma of the right adrenal gland. Transcatheter arterial embolization (TAE) was performed for the purpose of the treatment of hepatic metastases resistant to 27 cycles of combined chemotherapy consisting of cyclophosphamide, vincristine, and dacarbazine. After TAE, the hepatic metastatic lesions decreased in size and hypertension passed its crisis. The present case suggests the utility of TAE for multiple hepatic metastases under careful blood pressure monitoring.

Abstract: We treated a patient diagnosed as central nervous system (CNS) aspergillosis with the combined use of cerebral diffusion-weighted echo-planar magnetic resonance imaging (DWI) and polymerase chain reaction of the cerebrospinal fluid (CSF-PCR). DWI, a cutting-edge imaging modality to reveal the earliest changes of cerebral infarction, detected cerebral fungal embolization when the conventional computed tomographic scan and magnetic resonance imaging failed to reveal it. CSF-PCR demonstrated the presence of Aspergillus-specific DNA in the specimen, when the conventional examination and culture of CSF were nonspecific or negative. These diagnostic methods could be useful in the early diagnosis of CNS aspergillosis.

Abstract: During the past few years remarkable progress has been achieved in the understanding of the pathogenic mechanisms leading to vascular inflammation and injury in ANCA-associated vasulitides (AAV): Wegener's granulomatosis (WG), microscopic polyangiitis (MPA) and Churg Strauss syndrome (CSS). In this paper we review the immunopathology of these diseases by describing the role of autoantibodies (ANCA), dysregulation and abnormalities at the cellular level, genetic background and environmental factors that predispose to autoimmune response.

Abstract: We report a case of cerebral aspergillosis which originated from the sphenoid sinus, and involved a progressive decrease of visual acuity. The neurological signs indicated a cavernous sinus invasion. After extensive intracranial surgery we treated the residual aspergillosis with a high oral dose of itraconazole (800 mg/d for 4 months, followed by 400 mg/d for 5 months). The neurological impairments of the patient gradually subsided with the resolution of the fungal lesion shown on MRI. The successful therapy indicated that itraconazole has a significant role in the treatment of advanced cerebral aspergillosis if it is used in high doses (16 mg/kg/d for adults).

Abstract: A 41-year-old man with systemic lupus erythematosus (SLE) who developed pelvic inflammation due to perforation of a giant rectal ulcer is described. The patient presented with persistent diarrhea, abdominal pain and fever without development of disease activity of SLE. Endoscopic and radiological examinations revealed a perforated giant ulcer on the posterior wall at the rectum below the peritoneal evagination. The ulcerated area was decreased after a colostomy was performed at the transverse colon to preserve anal function. The patient is currently being monitored on an outpatient basis. It should be noted that life-threatening complications such as perforated ulcer of the intestinal tract could occur without SLE disease activity.

Abstract: Reactive arthritis is a member of the spondyloarthropathy. Bacteria which cause reactive arthritis infect the mucosal surfaces. Either the whole bacteria or their fragments are subsequently carried to the joints inside which are induced a TH1 lymphocyte response in which oligoclonal T lymphocytes as well peptide-specific CD8+ T lymphocytes participate. Human lymphocyte antigen (HLA)-B27 is a predisposing gene. Besides being determinants for the CD8+ T lymphocyte response it can also modify the response of other cells to the invasive bacteria. This would lead to alteration of the fate of the bacteria as well as release of arthritis-causing cytokines.

Abstract: We analyzed the clinical course of eight patients with liver dysfunction in measles. All of the patients showed an elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH), but no jaundice. These levels returned to normal about 3 weeks after the onset of the rash. A percutaneous liver biopsy was done in two cases. Histological examination showed slight necrosis of liver cells but no significant changes in portal area. On electron microscopy, virus particles were not detected. We detected measles virus RNA in the liver specimen by RT-PCR, which suggests that the measles virus affects liver cells directly in measles.

Abstract: A 65-year-old pigeon breeder who presented with acute hypersensitivity pneumonitis refused to give up contact with pigeons and her lung disease, which had initially improved in hospital in response to removal from pigeons, progressed to chronic interstitial fibrosis. Bronchoalveolar lavage lymphocytes fell from 50.0% of total cells in December 1986 to 27.1% in February 1990. The ratio of CD4+/CD8+ lymphocytes shifted from 0.43 to 1.47. Furthermore, IL-6 and TNF-alpha were elevated initially and were much higher at the second time point. These data pointed to the importance of CD4+ lymphocytes, IL-6 and TNF-alpha in the development of pulmonary fibrosis.

Abstract: Systemic connective tissue diseases are characterized by the production of a number of autoantibodies directed against various cellular constituents. These autoantibodies are closely associated with certain diseases and clinical manifestations, and are therefore useful for clinical practice such as to diagnose diseases and to predict clinical subsets, disease activity and prognosis. To understand the etiology and pathogenic mechanisms of connective tissue diseases; it is particularly important to elucidate the structure and function of target autoantigens recognized by these disease-specific autoantibodies. In recent years, the nature of many target autoantigens have been identified using molecular biology approaches. Most of them are intracellular enzymes and regulatory factors necessary for important biological function involved in gene replication, transcription, RNA processing and protein translation. Thus, the studies of autoantibodies are useful not only in clinical medicine but also in basic cellular and molecular biology.

Abstract: Objective To evaluate the role of insulin resistance on coronary atherosclerosis, angiographic semiquantitative scores of coronary stenosis and calcification were evaluated. Subjects and Methods Ninety-five non-diabetic subjects with coronary arterial disease were selected from our angiographic data base. Hyperinsulinemia was defined as a serum insulin level of ≥60.4 IU/l at 120 minutes after 75 g oral glucose challenge. Results Twenty-three (24%) of the patients exhibited hyperinsulinemia. There was no difference in age or gender between the two subgroups. The incidence of hypertension, smoking habits, hypercholesterolemia, and hyperuricemia were also the same among the insulin resistance subgroups. Subjects with hyperinsulinemia had higher coronary artery scores of stenosis (11.9±5.6 vs 8.3±5.0, p<0.0001) and calcification (7.5±6.3 vs 4.8±4.9, p<0.0001). Moreover, the stenosis score had a close linear correlation with the 120 minutes serum insulin level (r=0.266, p=0.009), but not with the fasting level. Conclusion These results suggest that hyperinsulinemia is a risk for coronary arterial disease, and emphasize the severity of coronary atherosclerosis in normal glucose tolerant subjects.(Internal Medicine 38: 691-697, 1999)

Abstract: A 70-year-old woman with small-cell lung carcinoma (c-T4N2M0) was treated by six courses of combination chemotherapy (carboplatin and etoposide). After two weeks, she complained of a sense of darkness and night blindness. A Western blot analysis showed that the patient's serum bound with the recombinant 23-kDa retinal cancer-associated retinopathy (CAR) antigen at 1:1,000 dilution. Her visual acuity became so poor that she could only recognise a hand motion at 50 cm despite treatment with corticosteroids and combination chemotherapy. The patient was diagnosed as having a rare type of CAR because CAR is usually found before the diagnosis of primary cancer.

Abstract: Objective To clarify the extent of asymptomatic cerebrovascular involvement in systemic lupus erythematosus (SLE). Patients and methods Cerebral magnetic resonance imaging (MRI) findings and ultrasonography findings of 100 patients with SLE lacking present or past clinical neurologic deficits were compared with 66 age-matched volunteers to determine the combined intima-media thickness (IMT) of the common carotid artery, and tests for anti-cardiolipin antibodies (aCL). Results Thirty-eight patients, but only 2 controls, showed imaging abnormalities. Among 23 SLE patients with cerebrovascular lesions by MRI who underwent single-photon emission computed tomography (SPECT), 14 showed hypoperfusion of the lesion. The IMT value and prevalence of aCL did not differ between the 55 SLE patients tested and controls. SLE disease activity index (SLEDAI) as assessed by a quantitative clinical index was significantly greater in patients with brain lesions than in those without. Conclusion The prevalence of asymptomatic brain lesions in SLE patients is high, and shows a relationship to disease activity.(Internal Medicine 38: 785-795, 1999)

Abstract: A 79-year-old woman suffering from urinary incontinence and unsteady gait was diagnosed as having idiopathic normal pressure hydrocephalus (NPH) with hyponatremia due to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). The concentration of antidiuretic hormone was high while the plasma osmolality was low in the presence of concentrated urine during the episodes of hyponatremia. Magnetic resonance imaging (MRI) of the head showed enlargement of the third and lateral ventricles. After ventriculoperitoneal shunt surgery, the symptoms of NPH and hyponatremia improved. It may be possibly explained that mechanical pressure on the hypothalamus from the third ventricle is responsible for hyponatremia.