Estratégia cirúrgica na doença de Cushing em pacientes pediátricos: análise de 15 casos consecutivos operados em centro neurocirúrgico especializado

OBJECTIVE: The aim of this study was to review the results of surgery for pediatric patients with Cushing's disease who were less than 18 years old and underwent transsphenoidal surgery in a specialized center during a 25-year period. SUBJECTS AND METHODS: Retrospective study, in which the medical records, histology and pituitary imaging of 15 consecutive pediatric patients with Cushing's disease (mean age: 13 years) were evaluated by the same team of endocrinologists and a neurosurgeon from 1982 to 2006. Patients were considered cured when there was clinical adrenal insufficiency and serum cortisol levels were below 1. 8 µg/dL or 50 nmol/L after one, two, three, or seven days following surgery; they therefore required cortisone replacement therapy. Follow-up was for a median time of 11.5 years (range: 2 to 25 years). RESULTS: Clinical and biochemical cure was achieved in 9/15 patients (60%) exclusively after transsphenoidal surgery. Hypopituitarism was observed in four patients; growth hormone deficiency, in two; permanent diabetes insipidus, in one case. CONCLUSIONS: Cushing's disease is rare in children and adolescents. Transsphenoidal surgery is an effective and safe treatment in most of these patients. Plasma cortisol level < 1. 8 µg/dL following surgery is the treatment goal and is a good predictive factor for long-term cure of Cushing's disease.OBJETIVO: O objetivo deste estudo foi avaliar os resultados cirúrgicos em pacientes pediátricos com doença de Cushing com idade inferior a 18 anos, submetidos à cirurgia transfenoidal num centro especializado, durante um período de acompanhamento de 25 anos. SUJEITOS E MÉTODOS: Estudo retrospectivo dos prontuários médicos de 15 pacientes pediátricos com doença de Cushing (idade média de 13 anos), sendo avaliados aspectos clínicos, laboratoriais, histológicos e radiológicos. Todos os pacientes foram avaliados pela mesma equipe de endocrinologistas e operados por um mesmo neurocirurgião, entre 1982 e 2006. O tempo médio de seguimento foi 11,5 anos (2 a 25 anos). Os pacientes foram considerados curados quando houve insuficiência adrenal e níveis de cortisol plasmático inferiores a 1,8 µg/dL ou 50 nmol/L no pós-operatório um, dois, três ou sete dias após a cirurgia; estes pacientes necessitaram de reposição de corticosteroide. RESULTADOS: Cura clínica e bioquímica foi alcançada em 9/15 pacientes (60%) após a cirurgia transfenoidal. Hipopituitarismo foi observado em quatro pacientes; déficit de hormônio de crescimento, em dois; diabetes insípido permanente, em um. CONCLUSÕES: A doença de Cushing é rara na infância e na adolescência. A cirurgia transfenoidal é um tratamento efetivo e seguro para a maioria dos pacientes. Uma concentração de cortisol plasmático < 1,8 µg/dL nos primeiros dias pós-cirurgia transfenoidal é o objetivo do tratamento e um fator preditivo tardio para a cura da doença de Cushing

Effect of partial soil wetting on transpiration, vegetative growth and root system of young orange trees

The wetted area fraction is a factor critical to the success of drip irrigation. This study aimed to evaluate the effect of partial soil wetting on transpiration, vegetative growth and root system of young orange trees. The experiment was carried out in a greenhouse where plants were grown in 0.5 m3boxes internally divided into compartments. The wetting of 12 % of soil area was tested on two types of soil cultivated with ‘Valencia’ orange trees grafted onto Rangpur lime and ‘Swingle’ citrumelo rootstocks. Transpiration was determined in 40 plants. Water extraction and root density were evaluated in the compartments. Transpiration is reduced by restriction in wetted soil area, and such reduction is influenced by the number of days after the beginning of partial irrigation, atmospheric evaporative demand and plant phenological stage. Mean transpiration of plants with partial irrigation was equivalent to 84 % of the mean transpiration of plants with 100 % of wetted soil area in the period studied. However, after 156 days of imposing partial irrigation there was no difference in transpiration between treatments. Plant acclimation was caused by an increase in root concentration in the irrigated area. After a period of acclimation, if the entire root system is wetted, soil water extraction becomes proportional to the percentage of wetted area after a short period of time. Despite the reduction in transpiration, there was no difference between treatments with 12 % and 100 % of wetted soil area in terms of vegetative growth