PTH Spikes During Surgical Treatment for Secondary and Tertiary Hyperparathyroidism: A Prospective Observational Study.

BACKGROUND: The aim of the present study was to determine whether PTH spikes in renal hyperparathyroidism can interfere with the interpretation of intraoperative PTH monitoring and to determine its frequency and characteristics. METHODS: This was a prospective observational study of consecutive patients who underwent surgical treatment in a single tertiary institution. Patients were divided into two groups: spike and no spike. Patients with secondary and tertiary hyperparathyroidism were analyzed separately. Intraoperative PTH monitoring by venous serial samples: two samples were taken before the excision of the parathyroid gland, and two others were taken after resection. RESULTS: PTH spikes occurred in 23.5% (53 of 226), and their occurrence was similar between secondary and tertiary hyperparathyroidism patients (p = 0.074). The relative PTH spike intensity was higher in transplanted patients than in dialysis patients (55 vs. 20%, p = 0.029). A characteristic of the secondary hyperparathyroidism patients was the highest frequency of surgical failure (23 vs. 7.5%, p = 0.016) and the higher occurrence of supernumerary glands in the spike group (23 vs. 10.3%, p = 0.035). Supernumerary parathyroid was associated with surgical failure [19.1 (6.5-55.7) odds ratio [confidence interval], p < 0.001). In the studies evaluating the diagnostic test validity for patients on dialysis and experiencing spikes, the most significant impacts were in the sensitivity, accuracy, and negative predictive value of the method. CONCLUSIONS: PTH spikes occurred in up to 23.5% of renal hyperparathyroidism surgical treatments and can negatively influence the intraoperative parathyroid hormone monitoring. Regarding the phenomenon of PTH spikes, it is prudent to think about the possibility of a hyperplastic supernumerary gland.

Delayed sampling of intraoperative parathormone may be unnecessary during parathyroidectomy in kidney-transplanted and dialysis patients.

INTRODUCTION: Some authors advise in favor of delayed sampling of intraoperative parathormone testing (ioPTH) during parathyroidectomy in dialysis and kidney-transplanted patients. The aim of the present study was to evaluate the intensity and the role of delayed sampling in the interpretation of ioPTH during parathyroidectomy in dialysis patients (2HPT) and successful kidney-transplanted patients (3HPT) compared to those in single parathyroid adenoma patients (1HPT). METHODS: This was a retrospective study of ioPTH profiles in patients with 1HPT, 2HPT, and 3HPT operated on in a single institution. Samples were taken at baseline ioPTH (sampling at the beginning of the operation), ioPTH-10 min (10 minutes after excision of the parathyroid glands), and ioPTH-15 min (15 minutes after excision of the parathyroid glands). The values were compared to baseline. RESULTS: Median percentage values of ioPTH compared to baseline (100%) were as follows: 1HPT, ioPTH-10 min = 20% and ioPTH-15 min = 16%; 2HPT, ioPTH-10 min = 14% and ioPTH-15 min = 12%; 3HPT, ioPTH-10 min = 18% and ioPTH-15 min = 15%. DISCUSSION: The reduction was equally effective at 10 minutes in all groups. In successful cases, ioPTH decreases satisfactorily 10 minutes after parathyroid glands excision in dialysis and transplanted patients, despite significant differences in kidney function. The postponed sampling of ioPTH appears to be unnecessary.

Early postoperative parathormone sampling and prognosis after total parathyroidectomy in secondary hyperparathyroidism / Dosagem pós-operatória precoce de paratormônio e prognóstico, após paratireoidectoma total por hiperparatireoidismo secundário

Abstract Introduction: There is possibility of a supernumerary hyperplastic parathyroid gland in dialysis patients after total parathyroidectomy and autograft in dialysis patients. Objective: To test if the early postoperative measure of parathyroid hormone (PTH) can identify persistent hyperparathyroidism. Methods: A prospective cohort of dialysis patients submitted to parathyroidectomy had PTH measured up to one week after operation. The absolute value and the relative decrease were analyzed according to clinical outcome of satisfactory control of secondary hyperparathyroidism or persistence. Results: Of 51 cases, preoperative PTH varied from 425 to 6,964 pg/mL (median 2,103 pg/mL). Postoperatively, PTH was undetectable in 28 cases (54.9%). In eight individuals (15.7%) the PTH was lower than 16 pg/mL, in 10 (19.6%) the PTH values were between 16 and 87pg/mL, and in five (9.8%), PTH was higher than 87 pg/mL. Undetectable PTH was more common in patients with preoperative PTH below the median (p = 0.0002). There was a significant correlation between preoperative PTH and early postoperative PTH (Spearman R = 0.42, p = 0.002). A relative decrease superior to 95% was associated to satisfactory clinical outcome. A relative decrease less than 80% was associated to persistent disease, despite initial postoperative hypocalcemia. Conclusion: Measurement of PTH in the first days after parathyroidectomy in dialysis patients may suggest good clinical outcome if a decrease of at least 95% of the preoperative value is observed. Less than 80% PTH decrease is highly suggestive of residual hyperfunctioning parathyroid tissue with persistent hyperparathyroidism, and an early reintervention may be considered.

Resumo Introdução: Em pacientes renais crônicos dialíticos submetidos à paratireoidectomia total com autoenxerto, existe a possibilidade de uma glândula paratireoide hiperplásica residual. Objetivo: Verificar se a medida pós-operatória precoce do hormônio da paratireoide (PTH) após paratireoidectomia total com autoenxerto é útil para indicar uma glândula paratireoide residual ou supranumerária hiperplásica em pacientes dialíticos. Método: Em uma coorte prospectiva de pacientes em diálise submetidos a paratireoidectomia foi medido o PTH até uma semana após à operação. O valor absoluto e o decréscimo relativo foram analisados de acordo como desfecho clínico de controle satisfatório do hiperparatireoidismo ou persistência. Resultados: Em 51 casos, o PTH preoperatório variou entre 425 e 6.964pg/mL (mediana 2.103pg/mL). No pós-operatório, o PTH foi indetectável em 28 casos (54,9%). Em 8 indivíduos (15,7%), o PTH foi menor que 16pg/mL, em 10 (19,6%) os valores de PTH values estiveram entre 16 e 87pg/mL e em 5 (9.8%), o PTH foi superior a 87pg/mL. O PTH indetectável foi mais comum em pacientes com valor de PTH pré-operatório abaixo da mediana do PTH dos casos (p = 0,0002). Houve correlação significativa entre o PTH pré-operatório e o PTH pós-operatório precoce (Spearman R = 0,42, p = 0,002). Um decréscimo relativo superior a 95% associou-se a desfecho clínico satisfatório. O decréscimo relativo inferior a 80% associou-se à doença persistente, apesar de hipocalcemia inicial. Conclusões: A dosagem do PTH nos primeiros dias após à paratireoidectomia em pacientes dialíticos pode sugerir bom desfecho clínico quando há um decréscimo de pelo menos 95% em relação ao valor pré-operatório. O decréscimo inferior a 80% é indicativo de tecido paratireóideo residual com persistência do hiperparatireoidismo e uma reintervenção precoce pode ser considerada.

Early postoperative parathormone sampling and prognosis after total parathyroidectomy in secondary hyperparathyroidism.

INTRODUCTION: There is possibility of a supernumerary hyperplastic parathyroid gland in dialysis patients after total parathyroidectomy and autograft in dialysis patients. OBJECTIVE: To test if the early postoperative measure of parathyroid hormone (PTH) can identify persistent hyperparathyroidism. METHODS: A prospective cohort of dialysis patients submitted to parathyroidectomy had PTH measured up to one week after operation. The absolute value and the relative decrease were analyzed according to clinical outcome of satisfactory control of secondary hyperparathyroidism or persistence. RESULTS: Of 51 cases, preoperative PTH varied from 425 to 6,964 pg/mL (median 2,103 pg/mL). Postoperatively, PTH was undetectable in 28 cases (54.9%). In eight individuals (15.7%) the PTH was lower than 16 pg/mL, in 10 (19.6%) the PTH values were between 16 and 87pg/mL, and in five (9.8%), PTH was higher than 87 pg/mL. Undetectable PTH was more common in patients with preoperative PTH below the median (p = 0.0002). There was a significant correlation between preoperative PTH and early postoperative PTH (Spearman R = 0.42, p = 0.002). A relative decrease superior to 95% was associated to satisfactory clinical outcome. A relative decrease less than 80% was associated to persistent disease, despite initial postoperative hypocalcemia. CONCLUSION: Measurement of PTH in the first days after parathyroidectomy in dialysis patients may suggest good clinical outcome if a decrease of at least 95% of the preoperative value is observed. Less than 80% PTH decrease is highly suggestive of residual hyperfunctioning parathyroid tissue with persistent hyperparathyroidism, and an early reintervention may be considered.

Estudo biomecânico de membranas de biopolímero de cana de açúcar perfuradas e contínuas implantadas no celular subcutâneo da parede abdominal de ratos / Biomechanical study of continous films and meshes of sugercane biopolymer implanted in the abdominal wall subcutaneus tissue of the rats

A força máxima de tensão e deformação de membranas de biopolímero de cana-de-açúcar perfuradas e contínuas foram definidas antes e 180 dias após implantação no celular subcutâneo de ratos. Um grupo de 13 ratos Wistar foi anestesiado com cloridrato de xylasina 2, 0,5mL/kg de peso IM. Foi feito tricotomia da face ventral do abdome e em seguida anti-sepsia com iodopovidona. Sob condições de assepsia foi feito incisão de 6cm na pele sobre a linha mediana, divulsão do celular subcutâneo nos flancos direito e esquerdo. Em um lado foi colocado um fragmento de membrana de biopolímero de cana-de-açúcar perfurada de 3,0x2,0cm e no lado contra lateral um fragmento contínuo. Os ratos permaneceram em gaiolas individuais recebendo água e ração Labina® ad libitum. Ao completarem 180 dias do implante os ratos foram mortos com dose tóxica de anestésico e as membranas retiradas para ensaio mecânico em uma máquina universal de ensaios EMIC DL 500. Os resultados foram comparados com um nível de segurança de 95, utilizando-se o teste t de Student. A força máxima de tensão em Newton (N) das membranas contínuas antes da implantação 17,46 N foi maior que as membranas perfuradas 9,35 N, com significação estatística, p=0,026, não ocorrendo diferença entre as membranas perfuradas e contínuas após a implantação. O mesmo ensaio entre o pré, controle e o pós-operatório, experimental com as membranas perfuradas e contínuas não apresentou diferença com significação estatística. A deformação específica da força máxima () das membranas perfuradas como das contínuas foi maior após a implantação com significação estatística, p=0,001. O mesmo teste aplicado entre as membranas perfuradas e contínuas antes a após implantação não apresentou significação estatística. As membranas perfuradas apresentam uma força máxima à tensão menor que as membranas contínuas no pré-operatório. No pós-operatório tende a aumentar a força máxima à tensão...