Interstitial Granulomatous Drug Reaction to Ustekinumab.

Interstitial granulomatous drug reaction (IGDR) is a distinct inflammatory process that often presents as annular, violaceous plaques distributed on the extremities, proximal trunk, and intertriginous areas. The list of drugs implicated for inciting IGDR is growing, but most prominently includes ACE inhibitors, antihistamines, beta-blockers, antidepressants, and anticonvulsants. Ustekinumab is a human monoclonal antibody that targets inflammatory cytokines IL-12 and IL-23 and has been have shown to be effective in treating IGDR. However, we present a case that suggests ustekinumab can also act as an inciting agent for IGDR.

Darier disease, radiation therapy, and herpesvirus -- an unfortunate triad.

Darier disease (DD) is a rare autosomal dominant keratinizing disorder often characterized by brown scaly pruritic papules over the face, neck, and trunk. Herein is reported a patient who developed secondary cutaneous herpes simplex virus (HSV) following exacerbation of his DD as a result of radiation therapy. In November 2020, a 78-year-old man presented to clinic for a pruritic rash on his back consistent with DD. He had developed the rash after the conclusion of chemoradiation therapy for recently diagnosed urothelial carcinoma of the bladder with squamous differentiation. However, he returned two weeks later complaining of a marked worsening of the rash associated with a pain and burning sensations. Histopathology was non-conclusive, but the lesions were found to be positive for HSV-1 by PCR. The patient recovered without complication over a period of two weeks following a course of valacyclovir. There is precedent in the literature for ionizing radiation inducing flares of DD lesions in overlying skin. In addition, DD has been shown to put a patient at increased risk for secondary infections such as HSV. This case report demonstrates that HSV could pose a significant risk to those with DD receiving radiation therapy and thus could warrant prophylactic treatment.

Risk factors for reoperation due to chronic groin postherniorrhaphy pain.

BACKGROUND: Chronic groin postherniorrhaphy pain (CGPP) is common and sometimes so severe that surgical treatment is necessary. The aim of this study was to identify risk factors for being reoperated due to CGPP. METHODS: All 195,707 repairs registered in the Swedish Hernia Register between 1999 and 2011 were included in the study. Out of these, 28,947 repairs were excluded since they were registered as procedures on the same patient after a previous repair. Age, gender, hernia anatomy (indirect reference), method of repair (anterior sutured repair reference) and postoperative complications were included in a multivariate Cox analysis with reoperation due to CGPP as endpoint. RESULTS: Of the patients included in the study cohort, 218 (0.13%) later underwent reoperation due to CGPP, including 31 (14%) women. Median age at the primary repair was 61.5 years. Risk factors for being reoperated were age < median [hazard ratio (HR) 3.03, 95% confidence interval (CI) 2.22-4.12], female gender (HR 2.13, CI 1.41-3.21), direct hernia (HR 1.35, CI 1.003-1.81), other hernia (HR 6.03, CI 3.08-11.79), Lichtenstein repair (HR 2.22, CI 1.16-4.25), plug repair (HR 3.93, CI 1.96-7.89), other repair (HR 2.58, CI 1.08-6.19), bilateral repair (HR 2.58, CI 1.43-4.66) and postoperative complication (HR 4.40, CI 3.25-5.96). CONCLUSIONS: Risk factors for being reoperated due to CGPP in this cohort included low age, female gender, a direct hernia, a previous Lichtenstein or plug repair, bilateral repair and postoperative complications. Further research on how to avoid CGPP and explore the effectiveness of surgery for CGPP is necessary.

A prospective study of 100 roboticallyassisted laparoscopic adrenalectomies.

We evaluated robotically assisted laparoscopic adrenalectomy (RLA) in a prospective study of 100 consecutive patients (60 women and 40 men) undergoing unilateral adrenalectomy at the University Hospital. The median age was 59 (24-82) years and BMI 27.6 (17.1-40.9) kg/m(2). Preoperative diagnoses were Conn's syndrome 30%, pheochromocytoma 23%, Cushing syndrome 27% and non-functional tumor 20%. The median tumor size was 53 (10-106) mm. The majority of the 7% of the patients who were converted to open surgery were in the early phase after the introduction of the technique. The BMI of the patients who were converted to open surgery was significantly higher, 31.5 (range 25.3-37.8) compared to, 27.5 (range 17.1-40.9) in patients without conversion (P = 0.047). The median weight of the tumor was 51 g for patients with conversion (range 18-97 g) and 30 g (range 8-128 g) for patients without conversion (P = 0.066). The median console operation time for the whole series was 88 min (range 39-397 min). The console operation time decreased significantly with the numbers of patients operated (r = 0.372; P = 0.0003). There was an association between the weight of the specimen and operation time (r = 0.42; P = 0.0001). RLA is a safe and a feasible surgical alternative for treating all kind of adrenal disorders, particularly large tumors and more complex circumstances. The present study clearly shows that a learning curve is present for the console surgeon and assistants.

Randomized clinical trial comparing open with video-assisted minimally invasive parathyroid surgery for primary hyperparathyroidism.

BACKGROUND: : Previous studies of video-assisted techniques for parathyroidectomy in patients with primary hyperparathyroidism have found similar or better results compared with bilateral neck exploration. The aim of the present study was to compare open minimally invasive parathyroidectomy with the video-assisted technique for primary hyperparathyroidism in a multicentre randomized trial. METHODS: : Some 143 patients were randomized to open (n = 75) or video-assisted (n = 68) parathyroidectomy after positive sestamibi scintigraphy. There were no differences in preoperative data. The open operation was performed through a 15-mm incision. The video-assisted techniques used were minimally invasive video-assisted parathyroidectomy (MIVAP) or video-assisted parathyroidectomy using the lateral approach (VAPLA). Data were collected prospectively including postoperative pain scoring. RESULTS: : The procedure was significantly quicker for the open compared to the video assisted operations: mean(s.d.) 60(35) versus 84(47) min (P = 0.001). Both groups of patients had similar conversion rates and the same outcome, with comparable incision lengths, low scores for postoperative neck discomfort, high cosmetic satisfaction and low complication rates. CONCLUSION: : Open minimally invasive parathyroidectomy for primary hyperparathyroidism was quicker than either video-assisted technique. REGISTRATION NUMBER: NCT00877981 (http://www.clinicaltrials.gov)

Use of the harmonic scalpel versus conventional haemostatic techniques in patients with Grave disease undergoing total thyroidectomy: a prospective randomised controlled trial.

INTRODUCTION: Thyrotoxicosis is often considered to be the most difficult thyroid operation because of the high vascularisation and the risk of bleeding. The conventional haemostatic technique in thyroidectomy today include knot tying and electrocoagulation. The introduction of the harmonic scalpel (HS) has led to further research if the use of the HS has any benefits in thyroid surgery. To our knowledge, no previous study has evaluated the HS dissection technique in a homogenous group of patients with Graves' disease undergoing total thyroidectomy. MATERIALS AND METHODS: Fifty-one patients (39 women and 12 men) with the pre-operative diagnosis of Graves' disease treated at two endocrine centers were randomised to total thyroidectomy with the use of the HS or with conventional haemostatic techniques. RESULTS: Twenty-seven patients were randomised to the harmonic group and 24 to the conventional group. The operating time was shorter in the HS group (median, 121 min; range, 84-213 min) compared to the conventional group (median, 172 min; range, 66-268 min; p = 0.011). CONCLUSION: The use of the HS was associated with a significant reduction in operating time compared to the use of the conventional haemostatic techniques in patients with Graves' disease undergoing total thyroidectomy.

Melanoma and nonmelanoma skin cancer in patients with multiple tumours--evidence for new syndromes in a population-based study.

BACKGROUND: The hypotheses that Swedish patients with four or more primary tumours [including at least one cutaneous malignant melanoma (CMM)] harbour an increased number of CDKN2A (formerly p16) germline mutations, and that this group of patients show a predisposition to other tumours, e.g. nonmelanoma skin cancer (NMSC), were studied descriptively. So far the mutation 113insArg explains all CDKN2A-associated CMM in ethnic Swedes. OBJECTIVES: All patients with four or more primary tumours, of which at least one was a CMM, from the Southern Swedish Regional Tumour Registry, between 1958 and 1999, were included in this study. METHODS: Forty-four patients were found and subdivided into three groups according to having multiple CMM (group A) or single CMM +/- NMSC (groups B and C). Screening for the presence of the Swedish founder mutation 113insArg in blood or in tissue blocks was performed. RESULTS: Patients in group A were younger at the time of the first CMM diagnosis than patients in group B and group C. The 113insArg mutation was found in four of 44 patients (9%), three with multiple CMM. In group C (n = 14) no founder mutation was evident, while in group B (n = 15) one mutation carrier was found. Nonmutation carriers with multiple CMM (group A) also had a predilection for meningiomas and neurinomas (four patients) or multiple NMSC (three patients). In group B CMM were especially associated with adenocarcinomas but in group C CMM were associated with multiple NMSC. CONCLUSION: The association between meningiomas and neurinomas (no acoustic neurinoma was seen) might indicate a new syndrome. Patients in groups B and C may harbour unknown genetic defects, which could interact with different environmental risk factors.

Clinical and histopathological features of malignant melanoma in germline CDKN2A mutation families.

Primary cutaneous malignant melanomas (CMMs) from 26 individuals belonging to nine families with an identified mutation were clinically and histopathologically compared with 78 matched CMM controls and with a population-based series of CMMs ( = 667). All tumours were histopathologically re-examined. CDKN2A-associated cases were significantly less invasive compared with the matched controls, with an adjusted odds ratio (adjOR) of 2.9 and a 95% confidence interval (CI) of 1.0-8.1 ( = 0.04). According to the odds ratio (OR) values, CDKN2A-associated cases seemed to have tumours more often located on the head and neck (adjOR 2.9, 95% CI 0.6-13.7), with less inflammation (adjOR 0.7, 95% CI 0.3-1.8) and regression (adjOR 0.6, 95% CI 0.2-1.8) but more frequent histological ulceration (adjOR 1.9, 95% CI 0.6-5.8). In comparison with the population-based material, CDKN2A-associated cases were significantly younger at diagnosis (crude OR 3.5, 95% CI 1.6-7.5, divided at 50 years) and had less regressive reaction in their tumours (crude OR 0.35, 95% CI 0.2-0.8). No significant differences were seen for tumour thickness between the different groups. On multivariate analysis, the overall survival was significantly worse for thicker tumours and older age ( = 0.04 for both). To our knowledge this is the first description of the histopathological features of CMMs from families with mutations in the CDKN2A gene.

Prognostic factors in invasive cutaneous malignant melanoma: a population-based study and review.

A population-based study from Sweden identified 711 patients with cutaneous malignant melanoma diagnosed in 1965, 1975, 1985 and 1989. Prognostic factors were evaluated and a review of the literature was performed. On univariate analysis, thick tumours (> 0.8 mm) (odds ratio [OR] 1.8, 95% confidence interval [CI] 1.6-2.1), increasing Clark level (OR 1.8, 95% CI 1.6-2.0), ulceration (OR 1.8, 95% CI 1.6-2.0), nodular melanoma (OR 1.5, 95% CI 1.3-1.6) and increasing age (continuous variable, P < 0.0001) were associated with a shorter survival. Location on extremities (OR 0.8, 95% CI 0.7-0.9), inflammation (OR 0.8, 95% CI 0.7-0.9) and female gender (OR 0.8, 95% CI 0.8-0.9) were associated with improved survival. On multivariate analysis, thick tumours (> 0.8 mm) (OR 1.5, 95% CI 1.2-1.7) and ulceration (OR 1.4, 95% CI 1.2-1.6) were independently related to a poor prognosis, while location on extremities (OR 0.8, 95% CI 0.7-0.9), inflammation (OR 0.8, 95% CI 0.7-0.9) and female gender (OR 0.8, 95% CI 0.8-1.0) were associated with improved survival. No difference in mean tumour thickness was seen over time, but there was a significant increase in the percentage of thin melanomas (< 0.8 mm) in 1985 (P = 0.01) and 1989 (P = 0.002) compared with 1965. The incidence of melanomas with inflammation increased significantly (P = 0.04), as did age at diagnosis (P = 0.005).

Hemithyroidectomy: long-term effects on parathyroid function--preliminary report.

Early hypocalcemia after thyroid surgery has frequently been reported, whereas data regarding long-term effects on calcium homeostasis are scarce. We have previously studied patients after hemithyroidectomy with an oral calcium load test and found normal parathyroid hormone (PTH) suppression. However, the 1,25-dihydroxyvitamin D concentration was decreased and the phosphate concentration increased, implying parathyroid insufficiency. We therefore proceeded to investigate PTH secretion and suppression in 10 euthyroid patients subjected to hemithyroidectomy due to benign thyroid disease before and at 1 year after surgery. In addition, biochemical variables known to influence calcium homeostasis were analyzed. Basal, maximal, and total PTH secretion were unaltered 1 year postoperatively. However, maximal PTH secretion was reached at a lower serum level of ionized calcium, and there was a tendency toward increased parathyroid sensitivity to ionized calcium. Furthermore, compared to preoperative, total serum calcium, 1,25-dihydroxyvitamin D, and free thyroxine (T4) concentrations were decreased at follow-up. Total serum calcium and 1,25-dihydoxyvitamin D concentrations were decreased 1 year after hemithyroidectomy. These changes were not due to parathyroid insufficiency. Instead, our results imply increased parathyroid sensitivity to calcium and possibly reduced peripheral sensitivity to PTH.

Decreased levels of ionized calcium one year after hemithyroidectomy: importance of reduced thyroid hormones.

BACKGROUND: Previously we have found reduced levels of total serum calcium and 1,25(OH)2D3 despite an unaltered stimulated parathyroid hormone (PTH) secretion 1 year after hemithyroidectomy. The present study was undertaken to elucidate the possible relationship between calcium homeostasis, thyroid hormones and bone resorption in a group of 45 consecutive patients subjected to hemithyroidectomy because of a solitary nodule. All patients had free T4 and T3 levels within normal range preoperatively. METHODS: Thyroid hormones, bone mineral and biochemical variables known to reflect calcium homeostasis were studied. Patients were divided into three separate groups depending on their pre- and postoperative thyroid hormone status. RESULTS: One year postoperatively, serum levels of free T4 were decreased and that of thyrotropin (TSH) increased in the entire group of patients. The concentration of ionized calcium was reduced from 1.25 +/- 0.05 to 1.22 +/- 0.04 (p < 0.001) despite an unaltered PTH value (2.8 +/- 1.0 vs. 3.1 +/- 1.5, p = 0.50). A significant reduction in C-terminal telopeptide type 1 collagen (1CTP) indicated decreased bone resorption 1 year after surgery (p < 0.05). Subgroup analysis showed that a reduction in ionized calcium was seen only among patients with a postoperative decrease in free T4. Patients with subclinical hyperthyroidism preoperatively presented the lowest postoperative levels of ionized calcium, significantly reduced levels of 1CTP and increased levels of phosphate and creatinine. Multiple linear regression analysis showed that age (p < 0.05) and postoperatively changed serum levels of TSH (p < 0.05), creatinine (p < 0.05), phosphate (p < 0.001) and FT4 (p < 0.01) were independently associated with altered levels of ionized calcium. CONCLUSION: We conclude that the reduction in ionized calcium 1 year after hemithyroidectomy was not due to PTH deficiency. Instead our results suggest that the reduced effects of thyroid hormones on bone and kidney function is essential.

Urate and arteriosclerosis in primary hyperparathyroidism.

OBJECTIVE: An increased mortality due to cardiovascular disease has been reported in patients with primary hyperparathyroidism (pHPT). An association between urate and cardiovascular disease has been suggested. Metabolic abnormalities in pHPT may include urate. We therefore evaluated the metabolic arteriosclerotic risk profile in pHPT with special focus on the role of urate. DESIGN: Retrospective analysis of data before and 1 year after surgery for pHPT. PATIENTS: 130 consecutive patients, over the age of 44 years, who underwent surgery for pHPT. MEASUREMENTS: Biochemical variables known to reflect risk of arteriosclerotic disease (AD) and renal function tests including measurement of glomerular filtration rate (GFR) were investigated before and 1 year after surgery. RESULTS: pHPT patients with AD (n = 40) were older and had higher serum levels of urate and triglyceride, and more impaired renal function in comparison with patients without AD. PTH and calcium values did not differ. Multiple logistic regression analysis indicated that urate was an independent risk factor for AD in pHPT (P < 0.01). Three variables were shown to be positively associated with urate; male gender (P < 0.01), fasting blood glucose (P < 0.05) and serum level of triglyceride (P < 0.05). CONCLUSIONS: Urate was found to be an independent risk factor for arteriosclerotic disease in primary hyperparathyroidism. Serum level of urate could (in addition to gender) be associated with a metabolic disorder comprising increased glucose and triglyceride levels.

Peripheral effects of PTH are not altered after thyroid surgery in euthyroid patients.

BACKGROUND: We have previously found decreased serum levels of both ionized calcium and 1,25(OH)2D and an increase in serum phosphate levels at 1 year after hemithyroidectomy. However, basal and stimulated parathyroid hormone (PTH) secretions were not altered. To investigate whether the observed biochemical changes after unilateral thyroid surgery may be due to a relative end-organ resistance to PTH, we studied the peripheral effects of infused hPTH-(1-34) in 6 patients preoperatively and 3 months after hemithyroidectomy. METHODS: Serum levels of TSH, FT4 and FT3 were measured pre- and postoperatively. hPTH-(1-34) was infused at 0.9 IU/kg/h during 6 h. Blood samples for analysis of ionized calcium, intact PTH, phosphate, 25(OH)D, 1,25(OH)2D and urinary samples for calcium, phosphate and nephrogenous(n)-cAMP analysis were taken at baseline, when the infusion was discontinued after 6 h and at 24 h. RESULTS: Three months after hemithyroidectomy, serum levels of FT3 were decreased and TSH levels increased. Pre- and postoperative hPTH-(1-34) infusions induced increased serum levels of ionized calcium, 1,25(OH)2D, increased urinary excretion of phosphate and elevated n-cAMP levels. The changes in the studied biochemical variables during the hPTH-(1-34) infusions did not differ between the two study occasions. CONCLUSION: By using a 6-hour hPTH-(1-34) infusion protocol, we have shown that the peripheral PTH effect is not altered by a slight reduction in thyroid hormone levels at 3 months after hemithyroidectomy.

Postoperative elevated serum levels of intact parathyroid hormone after surgery for parathyroid adenoma: sign of bone remineralization and decreased calcium absorption.

Increased levels of intact parathyroid hormone (PTH) have been documented after surgery for primary hyperparathyroidism (pHPT) despite normocalcemia. The pathogenesis remains to be elucidated. Seventeen consecutive patients operated on for solitary parathyroid adenoma were investigated before and at 8 weeks and 1 year after surgery with serum levels of intact PTH, biochemical variables known to reflect PTH activity, and bone mineral content (BMC). In addition, an oral calcium loading test was performed 8 weeks after the operation. All patients had low or normal serum calcium levels during follow-up. Eight weeks after operation six patients (35%) had an increased serum PTH level. These patients (group I) preoperatively had higher serum levels of PTH and alkaline phosphatase than patients with normal PTH levels (group II). They also had lower BMC and larger parathyroid adenomas. They did not differ in renal function. At 8 weeks after operation group I showed higher mean serum levels of osteocalcin and propeptide of type I procollagen but lower urinary calcium excretion. In contrast to patients in group II, they also showed a lower calciuric response and a trend to a lower calcemic response during the oral calcium load. The two groups showed similar parathyroid sensitivity for calcium. Patients in group I demonstrated a significant increase in BMC the first year after the operation. Increased serum PTH 8 weeks after surgery for sporadic parathyroid adenoma was not due to persistent pHPT or impaired renal function. Instead, the results imply there is diminished calcium absorption and increased bone turnover with cortical bone remineralization.

High frequency of multiple melanomas and breast and pancreas carcinomas in CDKN2A mutation-positive melanoma families.

BACKGROUND: : Inherited mutations in the CDKN2A tumor suppressor gene, which encodes the p16(INK4a) protein, and in the cyclin-dependent kinase 4 (CDK4) gene confer susceptibility to cutaneous malignant melanoma. We analyzed families with two or more cases of melanoma for germline mutations in CDKN2A and CDK4 to elucidate the contribution of these gene defects to familial malignant melanoma and to the occurrence of other cancer types. METHODS: : The entire CDKN2A coding region and exon 2 of the CDK4 gene of an affected member of each of 52 families from southern Sweden with at least two cases of melanoma in first- or second-degree relatives were screened for mutations by use of polymerase chain reaction-single-strand conformation polymorphism analysis. Statistical tests were two-sided. RESULTS: : CDKN2A mutations were found in 10 (19%) of the 52 families. Nine families carried an identical alteration consisting of the insertion of arginine at position 113 of p16(INK4a), and one carried a missense mutation, in which the valine at position 115 was replaced with a glycine. The 113insArg mutant p16(INK4a) was unable to bind cdk4 and cdk6 in an in vitro binding assay. Six of the 113insArg families had at least one member with multiple primary melanomas; the 113insArg families also had a high frequency of other malignancies-in particular, breast cancer (a total of eight cases compared with the expected 2.1; P =.0014) and pancreatic cancer (a total of six cases compared with the expected 0.16; P<.0001). Families with breast cancer also had a propensity for multiple melanomas in females, suggesting that a sex-dependent factor may modify the phenotypic expression of CDKN2A alterations. CONCLUSIONS: : Our findings confirm that the majority of CDKN2A-associated melanoma families in Sweden are due to a single founder mutation. They also show that families with the CDKN2A 113insArg mutation have an increased risk not only of multiple melanomas and pancreatic carcinoma but also of breast cancer.

Sunscreen use and malignant melanoma.

In a new population-based, matched, case-control study from southern Sweden of 571 patients with a first diagnosis of cutaneous malignant melanoma, between 1995 and 1997, and 913 healthy controls aged 16 to 80 years, the association between sunscreen use and malignant melanoma was evaluated. The median sun protection factor (SPF) used by both cases and controls was 6, range 2 to 25. Sunscreen users reported greater sun exposure than non-users. Persons who used sunscreens did not have a decreased risk of malignant melanoma. Instead, a significantly elevated odds ratio (OR) for developing malignant melanoma after regular sunscreen use was found, adjusted for history of sunburns, hair color, frequency of sunbathing during the summer, and duration of each sunbathing occasion ¿OR = 1.8, 95% confidence interval (CI) 1.1-2.9]. The OR was higher in subjects who reported that sunscreen use enabled them to spend more time sunbathing (adjusted OR = 8.7, 95% CI 1.0-75.8 for always vs. never use). The association appeared to hold for subjects who did not suffer from sunburns while using sunscreens, for subjects who used SPF of 10 or lower, and among men. The pattern of a significantly increased melanoma risk was seen only for lesions of the trunk. Our results are probably related mainly to earlier sunscreens of low SPF. They substantiate the hypothesis that sunscreen use, by permitting more time sunbathing, is associated with melanoma occurrence.

Risk of cutaneous malignant melanoma in relation to use of sunbeds: further evidence for UV-A carcinogenicity.

In a population-based, matched, case-control study from southern Sweden of 571 patients with a first diagnosis of cutaneous malignant melanoma and 913 healthy controls aged 16-80 years, the association between sunbed use and malignant melanoma was evaluated. A total of 250 (44%) cases and 372 (41%) controls reported ever having used sunbeds. A significantly elevated odds ratio for developing malignant melanoma after regular exposure to sunbeds was found, adjusted for hair colour, raised naevi, skin type and number of sunburns (odds ratio (OR) 1.8, 95% confidence interval (CI) 1.2-2.7). A dose-response relationship between total number of sunbed uses and melanoma risk was only found up to the level of 250 times. The OR was higher in individuals younger than age 36 years (adjusted OR 8.1, 95% CI 1.3-49.5 for regular vs. never use). The association seemed to be true only for subjects with black/dark brown or light brown hair and among females. Lesions of the extremities showed the strongest association of increased risk with sunbed use. An increased risk was related to commercial exposure and to exposure during the winter. The results substantiate the hypothesis that exposure to sunbeds might increase the risk of developing malignant melanoma.

Risk factors for postoperative hypocalcemia after surgery for primary hyperparathyroidism.

HYPOTHESIS: A variety of clinical and biochemical variables may be associated with hypocalcemia after surgery for parathyroid adenoma. DESIGN: A prospective study of patients who underwent surgery for solitary parathyroid adenoma. SETTING: A university hospital department of surgery. PATIENTS: Eighty-six consecutive patients who underwent surgery for solitary parathyroid adenoma. INTERVENTION: Parathyroidectomy according to the principles of unilateral neck exploration. MAIN OUTCOME MEASURES: Clinical and biochemical risk factors for early (< or =4 days after surgery) and late (1 year after surgery) postoperative symptomatic and biochemical hypocalcemia. RESULTS: Twenty-two patients developed early symptomatic hypocalcemia. The difference in total serum calcium levels between patients, with and without early symptomatic hypocalcemia, was evident on the third and fourth postoperative days. Serum level of osteocalcin greater than 6.0 microg/L, bilateral neck exploration, and history of cardiovascular disease were risk factors for symptomatic hypocalcemia (odds ratios [95% confidence intervals]: 4.4 [1.4-14.1], 3.8 [1.3-11.6], and 0.1 [0.02-0.60], respectively). Patients with up to 1 risk factor had a possibility of only 7% to develop early symptomatic hypocalcemia. One year after surgery, 16 patients had low levels of total serum calcium (late biochemical hypocalcemia) and were asymptomatic. Preoperative intermittent hypercalcemia was associated with an increased risk for late biochemical hypocalcemia (odds ratio, 3.9; 95% confidence interval, 1.0-16.3). CONCLUSIONS: Clinical and biochemical risk factors for early and late postoperative hypocalcemia in patients who underwent surgery for solitary parathyroid adenoma were found. A clinically useful prognostic index for early symptomatic hypocalcemia was constructed using these risk factors.