Adipsia increases risk of death in patients with central diabetes insipidus.

Central diabetes insipidus (CDI) is caused by deficiency of arginine vasopressin, an antidiuretic hormone. Patients with CDI manifest polyuria which is usually compensated for by increases in water intake. However, some patients are not able to sense thirst due to the destruction of osmoreceptors in the hypothalamus. These adipsic CDI patients are easily dehydrated and the consequent dehydration could be life-threatening. The objective of this study was to investigate the prognosis of adipsic CDI patients. We have reviewed 149 patients with CDI in three hospitals using databases of the electronic medical recording systems, and examined whether adipsia could affect the morbidity and mortality in CDI patients with multivariable analyses. Twenty-three patients with CDI were adipsic while the remaining 126 patients were non-adipsic. The multivariate analyses showed that the incidence of serious infections which required hospitalization was significantly higher in the adipsic CDI patients compared to that in non-adipsic CDI patients (p <0.001). A total of 6 patients with CDI died during the follow-up (median duration; 60 months, range 1 to 132 months). Four of them were adipsic, three of whom died of infection. The statistical analyses revealed that the risk of death in adipsic CDI patients was significantly higher than in non-adipsic patients (p =0.007). It is thus suggested that adipsic CDI patients were susceptible to serious infections which could be the causes of death.

Severe hypercholesterolemia associated with decreased hepatic triglyceride lipase activity and pseudohyponatremia in patients after allogeneic stem cell transplantation.

A 55-year-old woman with Ph-negative acute lymphoblastic leukemia in primary induction failure received allogeneic peripheral blood stem cell transplantation from her HLA-compatible sister. Pseudohyponatremia developed due to extreme hypercholesterolemia of 4091 mg/dL accompanied by lipoprotein X and lipoprotein Y. The hypercholesterolemia was caused by cholestasis due to chronic GVHD and ischemic cholangiopathy. In addition, we found that hepatic triglyceride lipase (HTGL) activity was severely decreased, which could be another novel factor causing extreme hypercholesterolemia after allogeneic transplantation. The total cholesterol has been gradually decreasing followed by the improvement of cholestasis with bezafibrate, ursodeoxycholic acid and prednisone treatments, and by a slight increase in HTGL-protein. To our knowledge, this is the first report to describe the association of decreased HTGL with extreme hypercholesterolemia after allogeneic transplantation.

Detection of autoantibody to aldolase B in sera from patients with troglitazone-induced liver dysfunction.

Troglitazone is a thiazolidinedione antidiabetic agent with insulin-sensitizing activities that was withdrawn from the market in 2000 due to its association with idiosyncratic hepatotoxicity. To address the suspected autoantibody production associated with troglitazone, we investigated autoantibodies in sera from patients with type II diabetes mellitus with troglitazone-induced liver dysfunction. Two female patients (47- and 70-year-old) ceased taking troglitazone (400 mg/day) after 23.5 and 16 weeks, respectively, due to increased serum ALT. Using two-dimensional electrophoresis and amino acid sequence analyses, aldolase B was identified as an autoantigen that reacted with antibodies in sera from both patients. The titer of anti-aldolase B remained high for several weeks after stopping troglitazone administration. The mean reactivity of autoantibodies to aldolase B determined by ELISA with sera of patients with chronic hepatitis (n = 40) and liver cirrhosis (n = 40) was significantly higher (p < 0.05 and p < 0.001, respectively) than with sera of healthy subjects (n = 80). These findings suggest that liver injury may cause the appearance of autoantibodies to aldolase B which may then aggravate the hepatitis. In addition, the anti-aldolase B titer might indicate the severity of liver dysfunction.

Appearance of thyroid stimulating and blocking immunoglobulins after bone marrow transplantation: presentation of two contrasting cases.

Two acute leukemia cases who presented autoimmune thyroid diseases after bone marrow transplantation (BMT) are described with reference to the pathogenesis of their autoimmune clones. A 37-year old Japanese woman developed Graves' hyperthyroidism 39 months after allogeneic BMT for acute myeloid leukemia (AML) donated from her sister. Although both donor and recipient were euthyroid and negative for thyroid autoimmunity before BMT, the donor was positive for anti-nuclear and anti-single strand DNA autoantibodies. Studies on polymorphism for variable number of tandem repeat region of T-cell receptor gene suggested that the lymphocytes responsible for the hyperthyroidism were of donor origin. The second case was a 12-year-old Japanese schoolboy who presented nongoitrous hypothyroidism 2 years after autologous BMT for acute lymphoblastic leukemia (ALL). He had been clinically euthyroid before transplantation. Family history revealed that his mother and sister had a history of Graves' disease. His serum was positive for thyroid-stimulation blocking antibody. It is highly likely that the autoimmune process was activated after transient immune suppression during peri-BMT period in this patient. Pathogenesis, incidence, and observed time lag between BMT and development of autoimmune thyroid diseases were discussed.