Primary central nervous system lymphoma in childhood presenting as progressive panhypopituitarism.

We report a 15-year-old boy who had isolated central diabetes insipidus initially diagnosed at age 11 years. A brain magnetic resonance imaging (MRI) was normal at the time. At age 12 years, growth hormone (GH) testing was performed because of a decline in linear growth rate and demonstrated GH deficiency. After a repeat normal brain MRI, GH therapy was begun. Three years later, hormonal testing revealed prepubertal gonadotropins and low testosterone levels, free thyroxine index, and morning cortisol levels. Repeat brain MRI demonstrated a 9-mm enhancing lesion in the region of the pituitary stalk. The pathologic diagnosis was that of a high-grade malignant B-cell lymphoma, suggestive of Burkitt Lymphoma. Growth hormone therapy has not been associated with an increased incidence of lymphoma. This report underscores the need for vigilance in follow-up brain imaging and hormonal evaluation in children with diabetes insipidus, especially those with evolving anterior hormone deficiencies.

Oral glucose tolerance: relationship with hemoglobin A1c.

Fifty-two normal non-obese males and 77 male offspring of two diabetic parents, aged 15-72 years, were studied to identify possible reasons for discordance between the oral glucose tolerance test (OGTT) and hemoglobin A1c (Hb A1c). Subjects were classified into four study groups: group 1 (n = 83), normal OGTT and normal Hb A1c; group 2 (n = 19), normal OGTT and abnormal Hb A1c; group 3 (n = 9), abnormal OGTT and normal Hb A1c; and group 4 (n = 18), abnormal OGTT and abnormal Hb A1c. Glucose and insulin response were analyzed in each study group. Group 2 showed slightly higher mean glucose areas during the first 60 min of OGTT testing when compared with group 1 (P less than 0.01). Insulin levels, insulin areas and insulin/glucose regression coefficients on group 2 did not differ significantly from group 1 during OGTT. Group 3 showed significantly higher mean blood glucose levels than subjects in group 1 (P less than 0.0001) or group 2 (P less than 0.001), but significantly lower mean blood glucose levels than subjects in group 4 (P less than 0.04) throughout the OGTT. During the OGTT, group 3 showed marked absolute hyperinsulinism when compared with all other groups (P less than or equal to 0.002). Also, relative hyperinsulinism in group 3 was suggested by the elevated insulin/glucose regression coefficient (1.86 +/- 0.50) when compared with group 1 (1.17 +/- 0.09), group 2 (0.92 +/- 0.011) or group 4 (0.55 +/- 0.17) (P less than or equal to 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Limited joint mobility (LJM) of the hand in patients with diabetes mellitus: relation to chronic complications.

Limited joint mobility (LJM) of the hand was studied by visual examination in 361 diabetic outpatients aged 11 to 83 years, and 45 non-diabetic controls, without evidence of arthritis. LJM was evident in 58% of diabetic subjects and 4% of controls (p less than 0.001). LJM was noted in 131 (55%) of the 238 patients with insulin-dependent diabetes mellitus (IDDM) as opposed to 31 of the 41 patients (76%) with non-insulin-dependent diabetes mellitus (NIDDM). LJM occurred in 60 of the 82 diabetic subjects (73%) receiving insulin therapy who developed diabetes after the age of 35 years. LJM was significantly related to duration of diabetes in the patients with IDDM less than 40 years of age but was not associated with duration in the patients with NIDDM. A significant association of LJM and neuropathy was noted in patients less than 40 years of age with less than 20 years of diabetes. A significant association of LJM and retinopathy was also noted in those less than 40 years of age with less than 30 years of diabetes. There was no association of LJM and nephropathy regardless of age or duration of diabetes.

Effect of acute blood loss on glycosylated hemoglobin determinations in normal subjects.

Nondiabetic adult subjects (N = 12) were studied to determine the effect of an approximately 450-ml acute blood loss upon glycosylated hemoglobin measurements. After blood loss, the hematocrit significantly decreased by week 1 (P less than 0.001) and the reticulocyte count peaked by week 2. All glycosylated hemoglobins measured showed significant decreases post blood loss. The nadir was at week 4 for total A1, A1c, and irreversible A1c by high-pressure liquid chromatography (HPLC), and at week 6 for irreversible A1 by HPLC and A1 by electrophoresis. The mean percent decrease in glycosylated hemoglobins ranged from 4.6% (irreversible A1 by HPLC) to 8.6% (total A1c by HPLC).