Granulocyte-Colony-Stimulating Factor Effectively Shortens Recovery Duration in Anti-Thyroid-Drug-Induced Agranulocytosis: A Systematic Review and Meta-Analysis

Antithyroid drug-induced leukopenia and G-CSF administration: a long-term cohort study

Although antithyroid drug (ATD)-induced agranulocytosis is a significant concern, its risks associated with long-term use and re-administration are not fully elucidated. Therefore, we performed this study to determine the incidence of ATD-induced leukopenia and G-CSF administration using administrative claims database. Retrospective cohort study. This study was performed using the DeSC Japanese administrative claims database. A total of 12,491 patients with newly diagnosed Graves' disease (GD) who received methimazole or propylthiouracil between April 2014, and February 2021 among 3.44 million patients in the database were included in the study. We measured the six-year incidence of leukopenia and granulocyte colony-stimulating factor (G-CSF) administration. The incidence of leukopenia and G-CSF administration was 1.34% (168 patients) and 0.30% (38 patients), respectively. Leukopenia had a dose-dependent and biphasic incidence. The incidence of leukopenia and G-CSF administration was 37.2 (0.7%) and 8.0 (0.2%) per 1000 person-years during the first 72 days of ATD initiation, whereas it was 3.1 and 0.7 per 1000 person-years during the subsequent 6 years, respectively. The incidence of both outcomes was comparable between first administration and re-administration of ATD. The incidence of ATD-induced leukopenia and G-CSF administration was high in the first 72 days, with a reduced risk for at least 6 years thereafter. The incidence was similar between first administration and re-administration. ATD, a standard therapy, is often administered for a long period; therefore, our findings can guide the treatment of GD.

Antithyroid Drug-Induced Agranulocytosis: A Case Report

Agranulocytosis is a rare but life-threatening complication of methimazole and propylthiouracil, antithyroid drugs (ATDs) prescribed for the treatment of hyperthyroidism. We report the case of a 41-year-old female who presented to our institution with complaints of fevers, chills, sore throat, myalgias, and generalized weakness one month after treatment initiation with methimazole. A complete blood count at admission revealed agranulocytosis with an absolute neutrophil count of 0/μl. After discontinuation of the medication, she was treated with granulocyte-colony stimulating factor and intravenous broad-spectrum antibiotics, which improved her condition on day seven of hospitalization. Although agranulocytosis is a rare complication of antithyroid drugs, providers must maintain a high index of clinical suspicion as prompt diagnosis and treatment are essential. After the diagnosis is confirmed with an absolute neutrophil count <500/μl, management involves discontinuation of the offending agent and initiation of intravenous broad-spectrum antibiotics. Granulocyte-colony stimulating factor, commonly employed in addition to antibiotics, is a controversial treatment option and more research demonstrating its efficacy is necessitated. Preventing mortality associated with antithyroid drug-induced agranulocytosis is achieved through patient education at the time of ATD initiation.

Therapeutic Management and Long-Term Outcome of Hyperthyroidism in Patients with Antithyroid-Induced Agranulocytosis: A Retrospective, Multicenter Study

BACKGROUND

Antithyroid drug-induced agranulocytosis (AIA) (neutrophils <500/µL) is a rare but serious complication in the treatment of hyperthyroidism.

METHODOLOGY

Adult patients with AIA who were followed up at 12 hospitals in Spain were retrospectively studied. A total of 29 patients were studied. The etiology of hyperthyroidism was distributed as follows: Graves' disease (n = 21), amiodarone-induced thyrotoxicosis (n = 7), and hyperfunctioning multinodular goiter (n = 1). Twenty-one patients were treated with methimazole, as well as six patients with carbimazole and two patients with propylthiouracil.

RESULTS

The median (IQR) time to development of agranulocytosis was 6.0 (4.0-11.5) weeks. The most common presenting sign was fever accompanied by odynophagia. All of the patients required admission, reverse isolation, and broad-spectrum antibiotics; moreover, G-CSF was administered to 26 patients (89.7%). Twenty-one patients received definitive treatment, thirteen patients received surgery, nine patients received radioiodine, and one of the patients required both treatments. Spontaneous normalization of thyroid hormone values occurred in six patients (four patients with amiodarone-induced thyrotoxicosis and two patients with Graves' disease), and two patients died of septic shock secondary to AIA.

CONCLUSIONS

AIA is a potentially lethal complication that usually appears around 6 weeks after the initiation of antithyroid therapy. Multiple drugs are required to control hyperthyroidism before definitive treatment; additionally, in a significant percentage of patients (mainly in those treated with amiodarone), hyperthyroidism resolved spontaneously.

Clinical characteristics of neutropenic patients under antithyroid drug: Twelve-year experience in a medical center

BACKGROUND

Thionamide-induced agranulocytosis (TiA) is a rare adverse event with a reported incidence of approximately 0.1% to 1.75%. Prompt recognition of TiA is critical to reduce the mortality rate. However, the differential diagnosis between cases of TiA and non-TiA neutropenia can be challenging due to the potential simultaneous involvement of other causes of neutropenia, such as concomitant chemotherapy, liver dysfunction, or infection. The aim of the present study was to investigate the possible factors associated with the development of TiA.

METHODS

This was a retrospective cohort study of patients treated with antithyroid drugs (ATDs) in Taipei Veterans General Hospital, Taipei, Taiwan, from 2006 to 2018. Patients who developed a neutropenic event during treatment with ATDs were identified from their medical records. The diagnosis of TiA was based on the following: (1) development of neutropenia during treatment or within 7 days after previous exposure to the same ATDs; (2) complete resolution of neutropenia within 1 month after discontinuation of the culprit drug with an absolute neutrophil count (ANC) >1500/μL; and (3) exclusion of other causes of neutropenia. The incidence and risk factors of TiA were analyzed and compared with those of non-TiA neutropenia.

RESULTS

Among 6644 patients treated with ATDs, 66 (mean age: 53 ± 15 years; 16.2% men) developed a neutropenic event and 20 were diagnosed with TiA (incidence: 0.3%). In the univariate analysis, compared with non-TiA neutropenia, TiA was associated with a lower Charlson Comorbidity Index, shorter treatment duration, lower cumulative ATD dosage, higher ATD dosage, higher ANC, and higher levels of free T4 at the time of the neutropenic event. In the multivariate logistic regression analysis, after adjusting for age, gender and the time to neutropenia, the cumulative ATD dose to neutropenia and ATD dosage at the time of the neutropenic event, Charlson Comorbidity Index, free T4 levels (odds ratio [OR], 4.44; 95% CI, 1.48-13.25), and ANC (OR, 1.00; 95% CI, 1.00-1.01) remained independently associated with TiA.

CONCLUSION

Patients with TiA were more likely to have higher levels of free T4 and ANC at the time of the neutropenic event vs those with non-TiA neutropenia.

How I manage inpatient consultations for quantitative neutrophil abnormalities in adults

Neutrophilia and neutropenia commonly lead to inpatient hematology consultation. Quantitative neutrophil abnormalities have a broad differential and include diagnoses that are important to recognize because they may be associated with increased mortality. Neutrophilia can reflect etiologies such as infection, medications, inflammation, splenectomy, and congenital disorders. Neutropenia can arise from infection, medications, autoimmune destruction, sequestration, nutritional deficiency, malignancy, and congenital neutropenia syndromes. In the evaluation of all abnormalities of neutrophil number, the timing of the change, and the patient's historical neutrophil count are crucial.

Association between radioactive iodine uptake and neutropenia in untreated Graves' disease

Objective

Neutropenia is a complication of Graves' disease (GD), but there is currently no means by which to predict its occurrence. This study aimed to investigate the risk factors for the development of neutropenia in untreated GD.

Methods

This was a retrospective cohort study. Between January 1, 2010, and July 31, 2020, 1000 patients with new-onset or relapsing GD without treatment were enrolled in the study and divided into two groups: neutropenia group (neutrophil count < 2 × 109/L) and non-neutropenia group (neutrophil count ≥ 2 × 109/L). Clinical characteristics of subjects were compared between the two groups, and logistic regression analysis was applied to determine risk factors for neutropenia. To further explore the correlation of radioactive iodine uptake (RAIU) with neutropenia, subjects were first classified according to quartile of 3 h RAIU and 24 h RAIU prior to logistic regression analysis.

Results

Of all patients recruited, 293 (29.6%) were diagnosed with neutropenia. Compared with non-neutropenic patients, those with neutropenia had a higher level of free thyroxine (FT4) (56.64 ± 31.80 vs 47.64 ± 39.64, P = 0.001), 3 h RAIU (55.64 ± 17.04 vs 49.80 ± 17.21, P < 0.001) and 24 h RAIU (67.38 ± 12.54 vs 64.38 ± 13.58, P < 0.001). Univariate logistic regression analysis revealed that FT4, 3 h RAIU, 24 h RAIU, creatinine, and low-density lipoprotein were risk factors for development of neutropenia in GD. After adjusting for confounding factors of age, BMI, and sex, we determined that 3 h RAIU and 24 h RAIU (Model 1: OR = 1.021, 95% CI: 1.008-1.033, P = 0.001; Model 2: OR = 1.023, 95% CI: 1.007-1.039, P = 0.004), but not FT4, were associated with the development of neutropenia.

Conclusions

RAIU is associated with neutropenia in patients with untreated GD.

Thyroid hormones and carnitine in the second trimester negatively affect neonate birth weight: A prospective cohort study

BACKGROUND

Maternal thyroid hormones and carnitine are reported to affect neonate birth weight during the second trimester, which is one of the most important markers for fetal growth and perinatal mortality and morbidity. Nevertheless, the effect of thyroid hormone and carnitine in the second trimester on birth weight has yet to be understood.

METHOD

This was a prospective cohort study with 844 subjects enrolled during the first trimester. Thyroid hormones, free carnitine (C0), neonate birth weight, as well as other related clinical and metabolic data were collected and assessed.

RESULTS

Pre-pregnancy weight and body mass index (BMI) as well as neonate birth weight were significantly different among different free thyroxine (FT4) level groups. Maternal weight gain and neonate birth weight varied significantly when grouped by different thyroid-stimulating hormone (TSH) levels. There was a significantly positive correlation between C0 and TSH (r = 0.31), free triiodothyronine (FT3) (r = 0.37), and FT4 (r = 0.59) (all P < 0.001). In addition, a significantly negative influence was found between birth weight and TSH (r = -0.48, P = 0.028), so as C0 (r = -0.55, P < 0.001) and FT4 (r = -0.64, P < 0.001). Further assessment detected a stronger combined effect of C0 and FT4 (P < 0.001) and of C0 and FT3 (P = 0.022) on birth weight.

CONCLUSION

Maternal C0 and thyroid hormones are of great importance in neonate birth weight, and routine examination of C0 and thyroid hormones during the second trimester has a positive effect on the intervention of birth weight.

Management of Graves' hyperthyroidism: present and future

INTRODUCTION

Graves' disease (GD) is an autoimmune disorder due to loss of tolerance to the thyrotropin receptor (TSHR) and ultimately caused by stimulatory TSHR antibodies (TSHR-Ab). GD may be associated with extrathyroidal manifestations, mainly Graves' orbitopathy. Treatment of GD relies on antithyroid drugs (ATDs), radioactive iodine (RAI), thyroidectomy. The major ATD limitation is the high recurrence rate after treatment. The major drawback of RAI and thyroidectomy is the inevitable development of permanent hypothyroidism.

AREAS COVERED

Original articles, clinical trials, systematic reviews, meta-analyses from 1980 to 2021 were searched using the following terms: Graves' disease, management of Graves' disease, antithyroid drugs, radioactive iodine, thyroidectomy, Graves' orbitopathy, thyroid-eye disease.

EXPERT OPINION

ATDs are the first-line treatment worldwide, are overall safe and usually given for 18-24 months, long-term treatment may decrease relapses. RAI is safe, although associated with a low risk of GO progression, particularly in smokers. Thyroidectomy requires skilled and high-volume surgeons. Patients play a central role in the choice of treatment within a shared decision-making process. Results from targeted therapies acting on different steps of the autoimmune process, including iscalimab, ATX-GD-59, rituximab, blocking TSHR-Ab, small molecules acting as antagonists of the TSHR, are preliminary or preclinical, but promising in medium-to-long perspective.