Indicações de paratireoidectomia no hiperparatireoidismo secundário à insuficiência renal crônica

Parathyroidectomy in chronic kidney disease: effects on weight gain and on quality of life improvement

Objective:

to evaluate the benefit of parathyroidectomy in patients on hemodialysis, regarding nutritional and biochemical statuses, body composition and the health-related quality of life.

Methods:

this is a longitudinal study involving 28 hemodialysis adult patients with severe secondary hyperparathyroidism evaluated before and one year after surgery. Inclusion criteria: parathyroid hormone levels exceeding ten times the upper normal range and end-stage renal disease in hemodialysis program. We used the body mass index to classify the nutritional status and the biodynamics analyzer to evaluate the body composition. Biochemical analysis included markers of lipid and bone metabolism. We assessed quality of life with the SF36 (Short Form Health Survey) questionnaire. All individuals underwent total parathyroidectomy with a forearm implant.

Results:

there were significant gains in body weight (61.7 vs 66.0 kg, p<0.001), body cell mass (22.0 vs 24.5 kg/m2, p=0.05) and quality of life (p=0.001) after surgery. With respect to bone metabolism, intact PTH, calcium, phosphorus and alkaline phosphatase all stabilized and there were improvements in biochemical parameters such as albumin and hemoglobin.

Conclusion:

parathyroidectomy improves hemodialysis patient survival and is associated with weight and bone cell mass gain and improvement in health-related quality of life.

Avaliação da capacidade da Escala Internacional de Eficácia de Quedas em discriminar risco de quedas em pacientes com doença renal crônica submetidos à hemodiálise

O objetivo deste estudo foi avaliar a capacidade da Escala Internacional de Eficácia de quedas (FES-I), dos níveis séricos de paratormônio (PTH) e do tempo de tratamento hemodialítico (TTH) de discriminar pacientes com doença renal crônica (DRC) em tratamento hemodialítico caidores de não caidores. Foi realizado estudo transversal com 64 pacientes, com idade média de 44,2±14,8 anos. Foram coletados dados antropométricos, níveis séricos de PTH, histórico e risco de quedas (Escala Internacional de Eficácia de Quedas - FES-I), TTH e o nível de atividade física (Questionário Internacional de Atividade Física - IPAQ). Foram encontrados níveis séricos de PTH elevados em 64,1% dos pacientes, e 17,2% deles relataram histórico de queda no último ano. O tempo médio de TTH foi 50,3±37,5 meses. Nível de atividade física leve foi encontrado em 64,1%. Foi encontrada correlação positiva entre o PTH e o TTH (r=0,47; p<0,001). Não foram encontradas correlação entre o FES-I e o PTH (p<0,131), entre o FES-I e o TTH (p<0,153) nem entre o PTH (valor baixo/normal <450 pg/mL e valor elevado >450 pg/mL) e o risco de queda (caidores e não caidores) (p<0,158). No estudo, o instrumento FES-I mostrou-se capaz de discriminar hemodialíticos caidores de não caidores. Concluímos que a FES-I apresentou bom desempenho de avaliação entre caidores e não caidores, no entanto não foi observada associação entre caidores com os níveis séricos do PTH e com o TTH.

Displasia renal em cão da raça Rotweiller

Descreveram-se os achados clínicos e patológicos de um caso de displasia renal em um cão da raça Rotweiller com oito meses de idade. O animal apresentou vômitos, emagrecimento, polidpsia e poliúria. Houve elevação sanguínea de creatinina, cálcio e da fosfatase alcalina. À necropsia, notaram-se os rins diminuídos de tamanho, com estruturas císticas proeminentes sobre a superfície natural do órgão e, ao corte, firmes e com estruturas císticas distribuídas pelo parênquima. Na avaliação histológica, havia glomérulos imaturos, fibroplasia intersticial e dilatação cística tubular.

Prevalence of radiological findings among cases of severe secondary hyperparathyroidism

CONTEXT AND OBJECTIVE

Patients with end stage renal disease (ESRD) and secondary hyperparathyroidism (HPT2) are prone to develop heterotopic calcifications and severe bone disease. Determination of the sites most commonly affected would decrease costs and patients' exposure to X-ray radiation. The aim here was to determine which skeletal sites produce most radiographic findings, in order to evaluate hemodialysis patients with HPT2, and to describe the most prevalent radiographic findings.

DESIGN AND SETTING

This study was cross-sectional, conducted in one center, the Hospital Universitário Clementino Fraga Filho (HUCFF), in Rio de Janeiro, Brazil.

METHODS

Whole-body radiographs were obtained from 73 chronic hemodialysis patients with indications for parathyroidectomy due to severe HPT2. The regions studied were the skull, hands, wrists, clavicles, thoracic and lumbar column, long bones and pelvis. All the radiographs were analyzed by the same two radiologists, with great experience in bone disease interpretation.

RESULTS

The most common abnormality was subperiosteal bone resorption, mostly at the phalanges and distal clavicles (94% of patients, each). 'Rugger jersey spine' sign was found in 27%. Pathological fractures and deformities were seen in 27% and 33%, respectively. Calcifications were presented in 80%, mostly at the forearm fistula (42%), abdominal aorta and lower limb arteries (35% each). Brown tumors were present in 37% of the patients, mostly on the face and lower limbs (9% each).

CONCLUSION

The greatest prevalence of bone findings were found on radiographs of the hands, wrists, lateral view of the thoracic and lumbar columns and femurs. The most prevalent findings were bone resorption and ectopic calcifications.

Ectopic and extranumerary parathyroid glands location in patients with hyperparathyroidism secondary to end stage renal disease

Supranumerary or ectopic parathyroid glands are the main cause of persistent hyperparathyroidism (HPT) in patients with end stage renal disease (ESRD) submitted to parathyroidectomy (PTx).

PURPOSE

To evaluate the prevalence and location of parathyroid glands in these patients.

METHODS

Thirty-five patients with ESRD and severe secondary hyperparathyroidism (HPT2) had been submitted to total PTx at HUCFF from December 2001 to July 2005. Surgery was always performed by the same surgeon, who described in details the location of the glands.

RESULTS

Sixteen patients (45.7%) had ectopic glands, which were also extranumerary in five of them (14.3%). The most common locations were the thyroid parenchyma (33.3%), thyroid-thymus conduit (18.5%), and thymus (14.8%). Before PTx, the sensibility of ultrasonography and scintigraphy with technetium-99m Sestamibi was low (48.3% and 35.3%, respectively). Moreover, 51.4% of the nodules found at US were thyroid nodules. However, 99mTc-Sestamibi was useful to identify ectopic glands in those two patients with persistent HPT after PTx.

CONCLUSION

The presence of extranumerary and ectopic parathyroid glands in HPT2 is sufficiently important to justify their exhaustive search. As the preoperative image exams present low sensibility to locate them, it is necessary to develop an exploratory routine embracing the most common sites of location.

Risk factors for decreased total body and regional bone mineral density in hemodialysis patients with severe secondary hyperparathyroidism

Hyperparathyroidism contributes significantly to decreased bone mineral density (BMD) in end-stage renal disease patients, but this negative influence is not homogeneous throughout the skeleton. We studied the BMD by dual-energy X-ray absorptiometry on total body and on different regions of the skeleton in 42 patients with severe hyperparathyroidism on hemodialysis. We also evaluated the relationship between different risk factors and BMD found on the regions examined in these patients. The legs and other sites where cortical bone predominate were mostly affected, whereas trabecular bone was relatively preserved. This is probably the result of the different effects of hyperparathyroidism on cortical and trabecular bone, but we cannot rule out the interference of ectopic calcifications and sclerotic lesions of vertebral end-plates falsely increasing lumbar spine BMD. The main determinants of low total-body BMD were, in order of importance, immobility, high intact parathyroid hormone levels, low body mass index, and low albumin. Eleven patients presented with pathologic fractures, mainly in the legs, and BMD was lower in this group than in patients without fractures. In conclusion, our study makes clear that hyperparathyroidism is a great threat to bone density in hemodialysis patients, mainly in the legs, the site mostly affected by fragility fractures in our patients. Physicians must worry not only with high parathyroid hormone levels, but also with the nutritional state of these patients.