The role of non-invasive dynamic tests in the diagnosis of Cushing's syndrome.

OBJECTIVE: To evaluate the role of non-invasive dynamic tests in the diagnosis and differential diagnosis of Cushing's syndrome (CS). METHODS: We studied laboratory features of 74 patients with endogenous CS, subdivided as follows: 46 (62.1%) with Cushing's disease (CD), 21 (28.3%) with an adrenal tumor, and 7 (9.5%) with ectopic ACTH syndrome (EAS). RESULTS: In 100% of cases of CS we found serum cortisol levels greater than 1.8 microg/dl after low-dose dexamethasone suppression tests (LDDST), as well as elevation of midnight serum or salivary cortisol. However, urinary free cortisol was normal in 11.5% of patients. ACTH levels were suppressed in patients with adrenal tumors, normal or high in CD and invariably increased in EAS. After the 8-mg overnight dexamethasone suppression test (HDDST), serum cortisol suppression >50% was observed in 79.5% of cases of CD and in 28.6% of subjects with EAS, whereas cortisol suppression >80% was only found in CD. After stimulation with CRH or desmopressin an ACTH rise > or =35% occurred in 86.5% of individuals with CD and 14.3% of those with EAS, whereas an ACTH rise > or =50 achieved 100% specificity. Moreover, the combination of serum cortisol suppression >50% after HDDST and an ACTH increase > or =35% after the administration of CRH or desmopressin only occurred in CD. CONCLUSION: Our findings demonstrate that LDDST had 100% sensitivity for the diagnosis of CS and that HDDST and stimulation tests with CRH or desmopressin may be very useful for confirmation of CS etiology when analyzed together or when more stringent cut-offs are used.

Retrospective study of a pioneer antenatal screening program with 8,477 pregnant women in Brazil.

PURPOSE OF INVESTIGATION: To analyze the results of a statewide screening program inaugurated in 2002 in Mato Grosso do Sul, METHODS: Retrospective audit of the screening results of 8,477 pregnant women for 11 diseases in 19 tests. Local health centers of the Brazilian Unified System of Health/State Program of Pregnant Protection (SUS/PEPG) and central reference processing laboratories, both in and out of state were involved. Pregnant women were referred to the program by medical staff principally at local health centers, between November 2002 and February 2003. Primary screening with filter-paper blood samples was carried out with positives being resampled and sera appropriately tested. RESULTS: The detailed test results are given below; the most frequent diseases serodiagnosed were hepatitis B, syphilis, HIV and Chagas' disease. One case of maternal phenylketonouria (PKU) was encountered. CONCLUSION: The diagnosis of 11 diseases of importance for mothers and their offspring provides an epidemiological profile of Brazil, but must be matched by opportunities to elaborate new control strategies and improve health care during pregnancy.