Reversible peripheral neuropathy in idiopathic hypoparathyroidism

Vertebral fractures, trabecular bone score and their determinants in chronic hypoparathyroidism

PURPOSE

Patients with hypoparathyroidism are at risk of vertebral fractures (VFs) despite high bone mineral density (BMD). We investigated this paradox by assessing trabecular bone score (TBS) and hip structural analysis (HSA) in non-surgical chronic hypoparathyroidism (cHypoPT) with and without VFs.

METHODS

152 cHypoPT patients (age 40.2 ± 13.4 years, M: F = 81:71) with a median follow-up of 8 (2-13) years were assessed for BMD, VFs, TBS, and HSA and compared with 152 healthy controls. VFs at T₇-L₄ were assessed by Genant's method. Average serum total calcium and phosphorus during follow-up were assessed.

RESULTS

The lumbar spine and hip BMD were higher by 25.4 and 13.4% in cHypoPT than controls (P < 0.001). Paradoxically, VFs (30.9 vs.7.9%), including multiple (12.5 vs. 2.6%) were higher in cHypoPT (P < 0.001). Though overall average TBS (1.411 ± 0.091) was normal in cHypoPT, 25.4% of the females had subnormal TBS, more in post than pre-menopausal women (52.3 vs. 14%, P = 0.002) and as compared to males (6.1%, P = 0.001). TBS correlated with menopausal status and follow-up serum calcium-phosphorus product. For every gm/cm² rise in BMD, TBS increase was only 0.227 in cHypoPT compared to 0.513 in controls. Frequency of VFs increased with declining TBS (P = 0.004). HSA was comparable between cHypoPT with and without VFs. 23.4% of cHypoPT with VFs had subnormal TBS.

CONCLUSION

31% of cHypoPT patients had VFs. TBS indicated degraded bone microarchitecture in 50% of the post-menopausal cHypoPT women. However, TBS has limitations to detect abnormal bone microarchitecture in cHypoPT as only one-fourth of patients with VFs showed low TBS.

Amyotrophic lateral sclerosis mimics

Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disorder characterized by progressive degeneration of cortical, bulbar, and spinal motor neurons. When a patient presents with a progressive upper and/or lower motor syndrome, clinicians must pay particular attention to any atypical features in the history and/or clinical examination suggesting an alternate diagnosis, as up to 10% percent of patients initially diagnosed with ALS have a mimic of ALS. ALS is a clinical diagnosis and requires the exclusion of other disorders that may have similar presentations but a more favorable prognosis or an effective therapy. Because there is currently no specific diagnostic biomarker that is sensitive or specific for ALS, understanding the spectrum of clinical presentations of ALS and its mimics is paramount. While true mimics of ALS are rare, the clinician must correctly identify these disorders to avoid the misdiagnosis of ALS and to initiate effective treatment where available.

Examination of Amorphous Calcium Carbonate on the Inflammatory and Muscle Damage Response in Experienced Resistance Trained Individuals

The effect of 3 weeks of amorphous calcium carbonate (ACC) supplementation (2000 mg per day) was examined on the recovery response to resistance exercise. Thirty men were randomized into a supplement (ACC) or placebo (PL) group. Following supplementation, participants performed six sets of 10 repetitions in the bench press (BP) and incline BP exercises, using 80% of maximal strength. Participants returned 24 (T4) and 48 h (T5) later and performed six sets of the BP exercise. Significant decreases in the number of repetitions (p < 0.001), peak power (p < 0.001), and mean power (p = 0.009) were noted over time, but no significant interactions were observed (p > 0.05). Magnitude-based inference analysis (MBI) indicated that the change in repetitions was possibly beneficial for ACC at T4 and likely beneficial at T5. No significant interaction was noted for general soreness (p = 0.452), but a trend toward an interaction was observed in upper body soreness (p = 0.089). Confidence intervals for mean percent change scores indicated significant differences between the groups at T4 and T5, and MBI analysis indicated that ACC was very likely or likely to be beneficial for reducing soreness at those time points. In conclusion, ACC supplementation may have a potential beneficial effect in attenuating the decline in performance, which is possibly due to the carbonate component.

Alfacalcidol vs Calcitriol in the Management of Patient With Hypoparathyroidism: A Randomized Controlled Trial

CONTEXT

Alfacalcidol and calcitriol are commonly used for managing hypoparathyroidism. Their relative merits have not been systematically assessed.

OBJECTIVE

We compared the effect of alfacalcidol and calcitriol on phosphatemic control, hypercalciuria, and associated factors in idiopathic-hypoparathyroidism (IH).

DESIGN AND SETTING

Open-label randomized controlled trial, tertiary care center.

SUBJECTS AND METHODS

IH patients with optimal calcemic control on alfacalcidol were continued on the same (n = 20) or switched to calcitriol (n = 25) at half of the ongoing alfacalcidol dose. The dose was adjusted during follow-up to maintain serum total calcium between 8.0 and 9.5 mg/dL. Serum calcium, phosphorus, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, 24-h urine calcium-to-creatinine ratio, and fractional excretion of phosphorus (FEPh) were measured at baseline and 6 months. Plasma intact-FGF23 was measured at final follow-up.

RESULT

Patients receiving alfacalcidol and calcitriol had comparable serum calcium at 6 months (8.7 ± 0.4 vs 8.9 ± 0.4 mg/dL, P = 0.13). Their median [interquartile range (IQR)] dose at 6 months was 2.0 (1.0-2.5) and 0.75 (0.5-1.0) µg/d, respectively. Serum 1,25(OH)2D levels were physiological in both (35.3 ± 11.6 and 32.3 ± 16.9 pg/mL). Serum phosphate and calcium excretion were comparable in 2 arms. A majority had hyperphosphatemia (75% vs 76%), hypercalciuria (75% vs 72%), and elevated FGF23 (116 ± 68 and 113 ± 57 pg/mL). Age showed significant independent association with plasma FGF23 (β = 1.9, P = 0.001). Average FEPh was low despite high FGF23.

CONCLUSION

At optimal calcium control, both alfacalcidol and calcitriol lead to comparable but high serum phosphate levels, hypercalciuria, physiological circulating 1,25(OH)2D, and elevated FGF23. Further studies are required to systematically investigate other treatment options.

Central Immune Tolerance of T and B Cells in Patients With Idiopathic Hypoparathyroidism, T1D, and Autoimmune Thyroiditis

CONTEXT

Pathogenesis of idiopathic hypoparathyroidism (IH) is under investigation. Abnormalities in central immune tolerance have yet not been investigated in this condition. T-cell receptor excision circles (TRECs) and kappa-deleting recombination excision circles (KRECs), formed during receptor gene rearrangements, are tools to assess central T- and B-cell output.

OBJECTIVE

We assessed the number of circulating TRECs and KRECs in patients with IH, autoimmune type 1 diabetes (T1D), and autoimmune thyroiditis (ATs) and healthy controls (HCs).

DESIGN

Comparative case-control at tertiary care center.

SUBJECTS AND METHODS

Absolute and relative TRECs and KRECs were measured in DNA extracted from whole blood of patients with IH (n = 181, 22 of whom were reassessed after a decade of follow-up) and T1D (n = 133), AT (n = 53), and HC (n = 135) using a quantitative real-time PCR/TaqMan® probe technique.

RESULTS

Absolute and relative means of TRECs and KRECs in IH were comparable to HCs, and no differences were found between IH with and without calcium-sensing receptor antibodies or class I HLA-A*26:01 association. TRECs and KRECs did not change after a decade of follow-up. T1D had significantly higher absolute TRECs than IH, AT, and HCs, whereas AT patients showed lower TRECs and the highest KRECs; these levels showed no noteworthy correlation with thyroid dysfunctions.

CONCLUSION

Patients with IH showed TRECs and KRECs comparable to HCs, indicating an intact mechanism of T- and B-cell central immune tolerance. Interestingly, absolute TRECs were significantly higher in T1D than HCs, suggesting impaired central immune tolerance in T1D.

Auditing the Efficacy and Safety of Alfacalcidol and Calcium Therapy in Idiopathic Hypoparathyroidism

CONTEXT

Patients with hypoparathyroidism are treated with vitamin D and calcium. PTH is an emerging option because of its physiological action. It is important to assess the efficacy and shortcomings of conventional therapy.

OBJECTIVE

We assessed the efficacy and safety of alfacalcidol in a large cohort of patients with idiopathic hypoparathyroidism (IH) and identified a subset who could be treated without oral calcium.

DESIGN AND SETTING

Observational study at tertiary care center.

SUBJECTS AND METHODS

We assessed 92 patients with IH who were receiving alfacalcidol and oral calcium to maintain an optimal serum total calcium level of 8.0 to 8.5 mg/dL during routine follow-up. Patients with suboptimal control were provided free medicines and followed up frequently. Oral calcium and alfacalcidol doses were titrated sequentially to determine the minimum doses for optimal calcium control. Serum phosphate level, 1,25-dihydroxyvitamin D, fractional excretion of phosphorus (FEPh), and hypercalciuria (urine calcium-to-creatinine ratio, >0.2) were assessed at each step of titration.

RESULTS

Only 38% of patients had optimal calcium control during routine follow-up. With good compliance, all achieved optimal serum calcium and 1,25-dihydroxyvitamin D levels and 43% of patients could stop taking oral calcium. Hyperphosphatemia, hypercalciuria, and low FEPh persisted at all stages of therapy. Serum phosphorus levels normalized when the serum calcium level increased to 9.9 mg/dL, but this level of serum total calcium was associated with hypercalciuria in 90% of patients.

CONCLUSION

Alfacalcidol is effective in achieving calcemic control in IH. Calcemic control without oral calcium was achieved in 43% of patients receiving alfacalcidol. However, optimal calcium control was associated with hyperphosphatemia and hypercalciuria in most patients.

Cardiovascular Autonomic Neuropathy as a New Complication of Postsurgical Chronic Hypoparathyroidism

Postsurgical hypoparathyroidism (hypoPT) increases fatigue and seems to affect the risk of mortality. Cardiovascular autonomic neuropathy (CAN) is an impairment of the cardiovascular autonomic system, a cause of increased mortality, and associated with increased fatigability. The aim of this study is to evaluate CAN in hypoPT and its relationship with hypocalcemia, PTH levels, and hyperphosphatemia. This is a cross-sectional study comparing 51 postsurgical hypoPT patients treated with calcium and calcitriol and 43 control subjects without any PTH/calcium/phosphate disorders who underwent thyroidectomy. CAN was assessed by heart rate (HR) response to deep breathing, HR response to the lying-to-standing test, HR response to the Valsalva maneuver, and blood pressure response to standing. Participants were considered to have "early CAN" if they had one abnormal result in the HR tests and "definite CAN" with two or more abnormal results. The prevalence of CAN was 23% in the control group and 78% in the hypoPT group (OR 11.48; 95% CI, 4.48 to 32.17). Patients with hypoPT and serum calcium (sCa) ≥8.5 mg/dL had a prevalence of early CAN of 72.4% and the prevalence was 86.4% in those with sCa <8.5 mg/dL. Definite CAN was found in 2.3% of the control group, 24.1% of the hypoPT group without hypocalcemia, and 59.1% of the hypoPT group with hypocalcemia. In the hypoPT group, the OR for definite CAN in the patients with hypocalcemia compared to the patients with normocalcemia was 4.54 (95% CI, 1.36 to 15.11). The association between low sCa and definite CAN was confirmed after adjustment for confounders with OR 13.62 (95% CI, 2.12 to 149.84). No association was found between definite CAN and PTH levels or high phosphate levels. HypoPT is associated with CAN and hypocalcemia seems to affect its severity. Larger and prospective studies are needed to confirm our findings. © 2018 American Society for Bone and Mineral Research.

Long-term outcome of cataract surgery in patients with idiopathic hypoparathyroidism and its relationship with their calcemic status

Cataract is a cardinal manifestation of hypoparathyroidism. Although patients with hypoparathyroidism require cataract surgery at a younger age than individuals without hypoparathyroidism, there is limited information on the outcome of this surgery. We assessed long-term complications of cataract surgery in patients with idiopathic hypoparathyroidism (IH) and its relationship with their clinical and biochemical parameters. Twenty-seven patients with IH and 25 nonhypoparathyroid controls with a minimum follow-up of 2 years after cataract surgery were assessed for visual acuity, intraocular pressure, lens centricity, Nd:YAG laser capsulotomy, and the severity of posterior capsular opacification (PCO) and anterior capsular opacification. High-resolution optical slit-lamp images were analyzed by an ophthalmologist. Patients with IH had cataract surgery at a younger age than controls (34.0 ± 16.4 years vs 58.0 ± 11.2 years, P < 0.001). A higher proportion of IH patients had dense white PCO (75.0 % vs 39.4 %, P = 0.004), Nd:YAG laser capsulotomy (44.2 % vs 10.0 %, P = 0.001), anterior capsular opacification (97.7 % vs 84.2 %, P = 0.03), and a decentric lens (28.3% vs 2.6 %, P = 0.001) at a comparable time after surgery (8.6 ± 6.1 years vs 8.7 ± 6.8 years, P = 0.85). On regression analysis, the severity of PCO in IH correlated only with male sex and not with other factors, including serum total calcium and inorganic phosphorus levels at the baseline and during follow-up. To conclude, patients with IH are likelier than individuals without IH to develop PCO and to require Nd:YAG laser capsulotomy after cataract surgery. Proper precautions should be taken during surgery to minimize this complication in IH.

The effect of vitamin D supplementation on pain, quality of life, and nerve conduction studies in women with chronic widespread pain

The aim of this study was to investigate the effects of vitamin D supplementation on pain, quality of life, and nerve conduction studies (NCSs) in women with chronic widespread pain (CWP) diagnosed with Vitamin D insufficiency. Thirty-three female participants with CWP and vitamin D insufficiency were included in this open-label trial. They were evaluated by routine NCSs in upper and lower limbs, pain scales, and the Nottingham Health Profile before and 8 weeks after starting vitamin D supplementation therapy. The P-value was adjusted to account for the number of comparisons performed in each assessment. After 8 weeks of treatment, participants reported significantly lower pain scores (P=0.000). The total Nottingham Health Profile score and subscores for pain, emotional reactions, and physical activity domains were significantly lower (0.000≤P≤0.008). However, no statistically significant changes in NCSs were detected, except trends toward increases in the amplitudes of left median and ulnar sensory nerve potentials and a decrease in the distal latency of the right median sensory potential (0.01≤P≤0.04). Vitamin D supplementation therapy decreased pain and increased quality of life without significantly affecting nerve conduction in patients with CWP.

Hypoparathyroidism: A rare mimic of amyotrophic lateral sclerosis

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) carries a grim prognosis. Various ALS mimics have been reported and should be excluded before confirming this diagnosis.

METHODS

We report the case of a 61-year-old man who presented with progressively worsening limb weakness and dysphagia. His examination showed mixed upper and lower motor neuron signs without sensory impairment. ALS was suspected, however, atypical diffuse pain prompted diagnostic work-up to exclude other causes.

RESULTS

Electrodiagnostic testing was suggestive of a sensorimotor polyneuropathy with superimposed diffuse active denervation suspicious for anterior horn cell degeneration. Brain MRI showed bilateral basal ganglia and thalamic calcifications. Laboratory studies confirmed the diagnosis of hypoparathyroidism. Treatment with calcium and vitamin D resulted in significant improvement at 6 months follow-up.

CONCLUSIONS

Hypoparathyroidism, a treatable endocrinopathy, can rarely present clinically as ALS. In atypical cases, this should be ruled out before making a final diagnosis. Muscle Nerve, 2016 Muscle Nerve 55: 437-439, 2017.

Menstruation associated hypocalcemic symptoms and serum calcium in patients with idiopathic hypoparathyroidism

BACKGROUND

Some of the patients with idiopathic hypoparathyroidism (IHP) report symptoms of hypocalcemia during menstruation. There is limited data on this observation.

METHODS

Twenty six menstruating women with IHP and 26 healthy controls were questioned regarding symptoms suggestive of hypocalcemia during menstruation. Twelve patients and eight controls were asked to prospectively monitor symptoms suggestive of hypocalcemia and premenstrual syndrome (PMS) if any, over two consecutive menstrual cycles. Serum ionized calcium (SiCa++), total and albumin adjusted calcium and intact paratharmone (iPTH) were measured at eight points covering menstrual, immediate post-menstrual, mid-cycle and premenstrual phase.

RESULTS

Twelve of the 26 (46.2%) patients with IHP reported hypocalcemic symptoms during menstruation as compared to none of the controls. During prospective monitoring, there was no specific trend of hypocalcemic symptoms with respect to the phase of menstrual cycle. The mean SiCa++, serum total and albumin-adjusted calcium, iPTH and inorganic-phosphorus measured over two menstrual cycles were not significantly different in either of the two study groups. None of the subjects had PMS.

CONCLUSION

Women with IHP do not show any trend of hypocalcemic symptoms or fluctuations in serum calcium over different phases of menstrual cycles. Therefore, patients with hypoparathyroidism linking hypocalcemic symptoms with menstruation should be reassured regarding lack of this association.

A possible correlation between vitamin D deficiency and loss of smell: 2 case reports

OBJECTIVE

The purpose of this report is to present 2 cases of diminished olfaction that improved with increasing serum levels of vitamin D3.

CLINICAL FEATURES

Both patients were under the care of medical and chiropractic physicians for various complaints. A 47-year-old hyposmic woman was diagnosed with vitamin D deficiency who incidentally noticed a progressive return of her sense of smell while taking vitamin D supplements as prescribed by her medical doctor. A 34-year-old anosmic woman noticed a direct relationship with her ability to smell and vitamin D3 supplementation.

INTERVENTION AND OUTCOME

Treatment for the first patient consisted of vitamin D supplementation of 10 000 IU a day. Her serum D3 levels increased substantially over a period of 8 months, at which time she reported a marked improvement in her sense of smell. The second patient was prescribed 50 000 IU of vitamin D a week; and she reported an increased ability to smell, although only the strongest of odors.

CONCLUSION

A link between hypovitaminosis D and a diminished sense of smell was noted in these 2 individuals.

Neuromuscular symptoms in a patient with familial pseudohypoparathyroidism type Ib diagnosed by methylation-specific multiplex ligation-dependent probe amplification

Pseudohypoparathyroidism type Ib (PHP-Ib) is a rare genetic disorder characterized by hypocalcemia and hyperphosphatemia due to imprinting defects in the maternally derived GNAS allele. Patients with PHP-Ib are usually identified by tetany, convulsions, and/or muscle cramps, whereas a substantial fraction of patients remain asymptomatic and are identified by familial studies. Although previous studies on patients with primary hypoparathyroidism have indicated that hypocalcemia can be associated with various neuromuscular abnormalities, such clinical features have been rarely described in patients with PHP-Ib. Here, we report a 12-year-old male patient with familial PHP-Ib and unique neuromuscular symptoms. The patient presented with general fatigue, steppage gait, and myalgia. Physical examinations revealed muscular weakness and atrophies in the lower legs, a shortening of the bilateral Achilles' tendons and absence of deep tendon reflexes. Laboratory tests showed hypocalcemia, hyperphosphatemia, elevated serum intact PTH level, and impaired responses of urinary phosphate and cyclic AMP in an Ellsworth-Howard test, in addition to an elevated serum creatine kinase level. Clinical features of the patient were significantly improved after 1 month of treatment with alfacalcidol and calcium. Methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) and subsequent PCR analyses identified a methylation defect at exon A/B of GNAS and a microdeletion involving exons 4-6 of the GNAS neighboring gene STX16 in the patient and in his asymptomatic brother. The results suggest that various neuromuscular features probably associated with hypocalcemia can be the first symptoms of PHP-Ib, and that MS-MLPA serves as a powerful tool for screening of GNAS abnormalities in patients with atypical manifestations.

Post-operative partial hypoparathyroidism: an under-recognized disorder

BACKGROUND

Permanent hypoparathyroidism is a well-recognized complication of total thyroidectomy, and a commonly reported clinical indicator of that procedure. However, a small number of patients still require ongoing calcium supplementation post-operatively in order to avoid the symptoms of hypocalcaemia, despite a normal serum parathyroid hormone level. The aim of this study was to characterize this disorder of post-operative partial hypoparathyroidism and to identify any risk factors.

METHODS

A retrospective study of patients undergoing a total thyroidectomy was performed. Patients with permanent hypoparathyroidism were excluded. Patients completed a telephone interview and had serum calcium and parathyroid hormone (PTH) measured. Patient demographics, operative indications and intervention, the number of parathyroid glands autotransplanted, the presence of ongoing symptoms and calcium requirements were documented.

RESULTS

One hundred ninety-six patients participated. The overall rate of permanent hypoparathyroidism over the duration of the study was 0.77%. An additional 10 (5%) patients were identified with a normal PTH level but who were still requiring calcium supplementation to prevent the symptoms associated with hypocalcaemia and to maintain a normal serum calcium level. Nine patients were female with a mean age of 48.5 years. A mean of 1.4 parathyroid glands were autotransplanted and the mean PTH level was 3.95 pmol/L.

CONCLUSION

This study demonstrates that in a small group of patients following total thyroidectomy, re-vascularization of parathyroid cells may be partial, with inadequate parathyroid reserve to avoid symptoms despite measurable PTH levels. This disorder of partial hypoparathyroidism has not been previously described and represents a small but important complication of total thyroidectomy.

A multicenter, double-blind, safety study of QR-333 for the treatment of symptomatic diabetic peripheral neuropathy. A preliminary report

BACKGROUND

QR-333, a topical compound that contains quercetin, a flavonoid with aldose reductase inhibitor effects, ascorbyl palmitate, and vitamin D(3), was formulated to decrease the oxidative stress that contributes to peripheral diabetic neuropathy and thus alleviate its symptoms. This proof-of-principle study assessed the efficacy and safety of QR-333 against placebo in a small cohort of patients with diabetic neuropathy.

METHODS

This randomized, placebo-controlled, double-blind trial included 34 men and women (21-71 years of age) with Type 1 or 2 diabetes and diabetic neuropathy who applied QR-333 or placebo (2:1 ratio), three times daily for 4 weeks, to each foot where symptoms were experienced. Five-point scales were used to determine changes from baseline to endpoint in symptoms and quality of life (efficacy). Safety was assessed through concomitant medications, adverse events, laboratory evaluations, and physical examinations.

RESULTS

QR-333 reduced the severity of numbness, jolting pain, and irritation from baseline values. Improvements were also seen in overall and specific quality-of-life measures. QR-333 was well tolerated. Eleven patients in the QR-333 group reported 23 adverse events (all mild or moderate); 4 in the placebo group reported 5 events (all moderate). One patient who applied QR-333 noted a pricking sensation twice, the only adverse event considered possibly related to study treatment.

CONCLUSIONS

From this preliminary safety study, it appears that QR-333 may safely offer relief of symptoms of diabetic neuropathy and improve quality of life. These findings warrant further investigation of this topical compound.