Radiotherapy-induced hypopituitarism in nasopharyngeal carcinoma: the tip of an iceberg

BACKGROUND

Radiation-induced hypopituitarism is an important late complication of cranial radiotherapy in children and adults. The purpose of this cross-sectional study was to evaluate the effects of radiotherapy on pituitary function in adult nasopharyngeal carcinoma patients.

METHODS

Pituitary function was evaluated in 30 patients after cranial radiotherapy for nasopharyngeal carcinoma. Somatotroph and corticotroph axes were assessed by insulin tolerance test while gonadotroph and thyroid axes were evaluated by basal pituitary and end organ hormone levels at 10-133 months after radiotherapy.

RESULTS

At least one hormonal disorder was observed in 28 (93%) patients after radiotherapy. 26 (87%) patients had one or more anterior pituitary hormone deficiencies. The rates of pituitary hormone deficiencies were 77% for growth hormone, followed by adrenocorticotropic hormone (73%), thyroid-stimulating hormone (27%) and gonadotropins (7%). Hyperprolactinemia was present in 13 (43%) patients.

CONCLUSIONS

Radiation-induced hypopituitarism is more common than expected in patients with nasopharyngeal carcinoma.

The role of ischemia modified albumin in acute pulmonary embolism

Background:

Acute pulmonary embolism (PE) is a life-threatening and a relatively common cardiovascular pathology. Although the pathogenesis of PE is well defined, there is no ideal diagnostic biochemical marker. Previous studies showed an increased ischemia modified albumin (IMA) levels in acute PE; however, the relationship between IMA and right ventricular (RV) dysfunction has not been examined. The aim of this study was to evaluate the diagnostic value of IMA and the relationship with RV dysfunction in acute PE.

MATERIALS AND METHODS:

A total of 145 patients (70 females) with suspected acute PE was enrolled to the study. Eighty-nine patients were diagnosed with acute PE via computed tomographic pulmonary angiography. Sixty-five patients with similar demographic and clinical characteristics were assigned to the control group. All patients were evaluated for RV dysfunction using transthoracic echocardiography.

Results:

Serum IMA levels were significantly increased in acute PE compared with control group (0.41 ± 0.06 vs. 0.34 ± 0.11, P = 0.001). There was no relationship between serum IMA levels and RV dysfunction. IMA levels were positively correlated with shock index and heart rate. Receiver operating curve analysis demonstrated that serum IMA levels higher than 0.4 put the diagnosis at sensitivity of 53.85% and at specificity of 85.96%.

Conclusions:

Although IMA levels are increased in patients with acute PE, it failed to predict RV dysfunction.

Levels of arginine and its products in dialysis patients

OBJECTIVES

Chronic renal failure is among significant public health problems all over the world. Despite advances in diagnosis and treatment approaches, cardiovascular morbidity and mortality is still high in chronic renal failure patients on dialysis. The aim this study is to investigate the importance of arginine, asymmetric dimethylarginine (ADMA) and nitric oxide (NO) levels in the pathophysiology of cardiovascular morbidity and mortality in patients with dialysis treatment program.

PATIENTS AND METHODS

53 patients with chronic renal failure receiving hemodialysis treatment and 34 healthy persons were participated to the study. Arginine and ADMA levels were measured by high-performance liquid chromatography (HPLC) fluorescence detector. NO levels were assessed by a colorimetric method. Albumin, urea, creatinine levels was performed using the spectrophotometric method.

RESULTS

Arginine levels were similar in dialysis patients when compared to the control group. Similarly NO levels did not show any difference between patient group and the control group. ADMA levels were found to be significantly high in dialysis patients compared to the control group (p < 0.005). Arginine/ADMA ratio was lower in the patient group compared to the control group (p < 0.001). Dialysis patients who have diagnosed coronary artery disease had low levels of albumin and creatinine. Arginine levels, ADMA levels and NO levels did not show any difference in the patients with coronary artery disease or not (p > 0.05). Arginine levels were significantly higher in men compared to women. Pearson correlation analysis showed that there was a correlation between NO and arginine levels. Arginine and Arginine/ADMA showed a positive correlation while ADMA and arginine/ADMA levels showed a negative correlation.

CONCLUSIONS

As a result, our data showed that ADMA clearance was impaired in hemodialysis patients. Increase in ADMA levels may play a role in atherosclerosis dependent morbidity and mortality.