Prepubescent unilateral gynecomastia secondary to excessive soy consumption

OBJECTIVE

We present a case of an unusual cause of prepubertal gynecomastia.

CASE PRESENTATION

Enlargement of breast tissue in males, or gynecomastia, is a rare condition in prepubescent boys. We describe an 8-year-old male who developed unilateral gynecomastia secondary to marked dietary soy consumption. While the majority of cases are idiopathic, soy products, particularly those consumed by our patient, can contain high levels of phytoestrogens, which have been documented in limited case studies to contribute to abnormal development of breast tissue in adolescent and adult males. To our knowledge, this is the first documented case of gynecomastia occurring in a prepubescent patient resulting from excessive intake of dietary soy. Importantly, we also report a complete resolution of gynecomastia upon exclusion of dietary products containing significant amounts of soy.

CONCLUSION

While soybeans and soy-derived products can be an important source of nutrition for some, those with abnormal sensitivity to phytoestrogens may benefit from limiting dietary soy consumption to avoid potential adverse effects, including gynecomastia.

Case Report of Thrombotic Thrombocytopenic Purpura in a Previously Healthy Adult

This case report details the presentation of a 24-year-old male presenting with headache, palpitations, gingival bleeding, and pallor. The ultimate diagnosis of thrombotic thrombocytopenic purpura (TTP) is a rare but life-threatening condition which is typically hallmarked by thrombotic microangiopathy (TMA) and dysfunctional ADAMTS13 enzymatic activity. This patient displayed classically described findings, including marked anemia, thrombocytopenia, and acutely elevated creatinine as well as a brief period of newly onset word-finding difficulty while in the emergency department. His diminished ADAMTS13 activity level (<5%) and the presence of autoantibodies against ADAMTS13 confirmed a diagnosis of TTP. Fortunately, the patient's outcome was favorable after treatment with plasmapheresis, prednisone, and rituximab. This case report provides a review of the clinical presentation, diagnostic criteria, potentially confounding differential diagnosis, and expected course of treatment for patients with TTP.

Topics

Thrombotic thrombocytopenic purpura (TTP), ADAMTS13, anemia.

Adult Clavicular Fracture Case Report

Clavicular fractures make up 2-4% of all fractures. While most are nondisplaced and easily managed, serious complications can arise from more severe fractures. In these cases, immediate surgical intervention is required. However, there lacks a consensus regarding the optimal treatment for fractures that are less severe. Here, we present a case of a 25-year-old male with a comminuted displaced mid-clavicular fracture. This report details the important clinical features of various types of clavicular fractures and discusses the current literature regarding indications for operative and nonoperative management.

Topics

Adult clavicular fracture; mid-clavicle fracture; orthopedics, trauma, upper extremity.

Mechanisms by Which Obesity Impacts Survival from Acute Lymphoblastic Leukemia

The prevalence of obesity has steadily risen over the past decades, even doubling in more than 70 countries. High levels of body fat (adiposity) and obesity are associated with endocrine and hormonal dysregulation, cardiovascular compromise, hepatic dysfunction, pancreatitis, changes in drug metabolism and clearance, inflammation, and metabolic stress. It is thus unsurprising that obesity can affect the development of and survival from a wide variety of malignancies. This review focuses on acute lymphoblastic leukemia, the most common malignancy in children, to explore the multiple mechanisms connecting acute lymphoblastic leukemia, obesity, and adipocytes, and the implications for leukemia therapy.

MON-058 Precocious Puberty and Hypothyroidism in a Pediatric Case

Background: Hypothyroidism with secondary sellar/suprasellar mass is rarely associated with precocious puberty. Here we describe a rare case of pediatric hyperprolactinemia and precocious puberty secondary to hypothyroidism, marked TSH elevation, and pituitary hyperplasia.

Clinical Case: A 9-year-old female, with onset of thelarche and menses occurring at age 7 and 8 respectively, presented with primary hypothyroidism (Free T4 &lt;0.11; n=4.9-11.4mcg/mL), elevated TSH (1620.0mU/mL; n=0.3-4.7mU/mL), hyperprolactinemia (108.6ng/mL; n=3.0-23.1ng/mL), and elevated serum estradiol (37.6pg/mL; n=10pg/mL). The patient had coarse scaly skin, diminished energy, and poor growth lasting 1 year. There were no associated gastrointestinal issues, temperature intolerance, nor visual impairments noted during this time.

Magnetic resonance imaging revealed a large mass (1.48cm) with suprasellar extension and a mass effect on the optic chiasm. The patient was then started on Levothyroxine and Cabergoline, to reduce serum prolactin levels. However, upon follow-up two months later, the patient had hypoprolactinemia (2.0ng/mL; n=3.0-23.1ng/mL). The patient was referred to neurosurgery for resection of the sellar mass. Endocrinology was also consulted, at which point Cabergoline was discontinued and Levothyroxine was gradually increased.

Follow up 4 months later showed prolactin levels had normalized to 11.4ng/mL (3.0-23.1ng/mL). Serum LH and FSH were within normal ranges (1.2mIU/mL and 4.2mIU/mL, respectively). TSH, though still elevated (47.35mU/mL; n=0.3-4.7mU/mL), was significantly reduced compared to the prior measurement (1620mU/mL). Serum levels of Free T4 increased to 1.06mcg/mL (n=4.9-11.4mcg/mL). Levothyroxine was titrated up and a repeated pituitary MRI demonstrated a significant decrease in the size of the mass with resolution of the suprasellar extension and mass effect on the optic chiasm. Further, the patient’s menses ceased and thelarche resolved upon correction of T4 and regression of the pituitary mass.

Conclusions: While rare, primary hypothyroidism and TSH-driven pituitary hyperplasia can result in a large mass effect with suprasellar extension, causing secondary hyperprolactinemia by a mass effect and central precocious puberty. This case highlights the benefits for evaluating underlying hypothyroidism as a cause for hyperprolactinemia and sellar/suprasellar mass.

Levocarnitine does not impair chemotherapy cytotoxicity against acute lymphoblastic leukemia

Asparaginase (ASNase) is an integral part of pediatric induction chemotherapy that has also been shown to improve adult survival rates; however, pegylated (PEG)-ASNase induces severe hepatotoxicity in this population. Recent case reports describe the incorporation of levocarnitine (LC) supplementation into PEG-ASNase-containing induction regimens to prevent or treat hepatotoxicity. Because LC facilitates the metabolism of free fatty acids (FFA), a primary fuel source for ALL cells, LC could potentially interfere with ALL chemotherapy efficacy. To test this, we employed in vitro and in vivo models of ALL. We show in vitro that LC supplementation does not impact cytotoxicity from vincristine, daunorubicin, dexamethasone, or ASNase on human ALL cells nor lead to an increase in ALL cell metabolic rate. In vivo, we demonstrate LC does not impair PEG-ASNase monotherapy in mice with syngeneic ALL. Together, our findings show that LC supplementation is a safe strategy to prevent/reverse ASNase-induced toxicities in preclinical models.

Concerted effects of heterogeneous nuclear ribonucleoprotein C1/C2 to control vitamin D-directed gene transcription and RNA splicing in human bone cells

Traditionally recognized as an RNA splicing regulator, heterogeneous nuclear ribonucleoprotein C1/C2 (hnRNPC1/C2) can also bind to double-stranded DNA and function in trans as a vitamin D response element (VDRE)-binding protein. As such, hnRNPC1/C2 may couple transcription induced by the active form of vitamin D, 1,25-dihydroxyvitamin D (1,25(OH)₂D) with subsequent RNA splicing. In MG63 osteoblastic cells, increased expression of the 1,25(OH)₂D target gene CYP24A1 involved immunoprecipitation of hnRNPC1/C2 with CYP24A1 chromatin and RNA. Knockdown of hnRNPC1/C2 suppressed expression of CYP24A1, but also increased expression of an exon 10-skipped CYP24A1 splice variant; in a minigene model the latter was attenuated by a functional VDRE in the CYP24A1 promoter. In genome-wide analyses, knockdown of hnRNPC1/C2 resulted in 3500 differentially expressed genes and 2232 differentially spliced genes, with significant commonality between groups. 1,25(OH)₂D induced 324 differentially expressed genes, with 187 also observed following hnRNPC1/C2 knockdown, and a further 168 unique to hnRNPC1/C2 knockdown. However, 1,25(OH)₂D induced only 10 differentially spliced genes, with no overlap with differentially expressed genes. These data indicate that hnRNPC1/C2 binds to both DNA and RNA and influences both gene expression and RNA splicing, but these actions do not appear to be linked through 1,25(OH)₂D-mediated induction of transcription.

Suppression of iron-regulatory hepcidin by vitamin D

The antibacterial protein hepcidin regulates the absorption, tissue distribution, and extracellular concentration of iron by suppressing ferroportin-mediated export of cellular iron. In CKD, elevated hepcidin and vitamin D deficiency are associated with anemia. Therefore, we explored a possible role for vitamin D in iron homeostasis. Treatment of cultured hepatocytes or monocytes with prohormone 25-hydroxyvitamin D or active 1,25-dihydroxyvitamin D decreased expression of hepcidin mRNA by 0.5-fold, contrasting the stimulatory effect of 25-hydroxyvitamin D or 1,25-dihydroxyvitamin D on related antibacterial proteins such as cathelicidin. Promoter-reporter and chromatin immunoprecipitation analyses indicated that direct transcriptional suppression of hepcidin gene (HAMP) expression mediated by 1,25-dihydroxyvitamin D binding to the vitamin D receptor caused the decrease in hepcidin mRNA levels. Suppression of HAMP expression was associated with a concomitant increase in expression of the cellular target for hepcidin, ferroportin protein, and decreased expression of the intracellular iron marker ferritin. In a pilot study with healthy volunteers, supplementation with a single oral dose of vitamin D (100,000 IU vitamin D2) increased serum levels of 25D-hydroxyvitamin D from 27±2 ng/ml before supplementation to 44±3 ng/ml after supplementation (P<0.001). This response was associated with a 34% decrease in circulating levels of hepcidin within 24 hours of vitamin D supplementation (P<0.05). These data show that vitamin D is a potent regulator of the hepcidin-ferroportin axis in humans and highlight a potential new strategy for the management of anemia in patients with low vitamin D and/or CKD.

Fibroblast growth factor 23 inhibits extrarenal synthesis of 1,25-dihydroxyvitamin D in human monocytes

Vitamin D is a potent stimulator of monocyte innate immunity, and this effect is mediated via intracrine conversion of 25-hydroxyvitamin D (25OHD) to 1,25-dihydroxyvitamin D (1,25(OH)(2) D). In the kidney, synthesis of 1,25(OH)(2) D is suppressed by fibroblast growth factor 23 (FGF23), via transcriptional suppression of the vitamin D-activating enzyme 1α-hydroxylase (CYP27B1). We hypothesized that FGF23 also suppresses CYP27B1 in monocytes, with concomitant effects on intracrine responses to 1,25(OH)(2) D. Healthy donor peripheral blood mononuclear cell monocytes (PBMCm) and peritoneal dialysate monocyte (PDm) effluent from kidney disease patients were assessed at baseline to confirm the presence of mRNA for FGF23 receptors (FGFRs), with Klotho and FGFR1 being more strongly expressed than FGFR2/3/4 in both cell types. Immunohistochemistry showed coexpression of Klotho and FGFR1 in PBMCm and PDm, with this effect being enhanced following treatment with FGF23 in PBMCm but not PDm. Treatment with FGF23 activated mitogen-activated protein kinase (MAPK) and protein kinase B (Akt) pathways in PBMCm, demonstrating functional FGFR signaling in these cells. FGF23 treatment of PBMCm and PDm decreased expression of mRNA for CYP27B1. In PBMCm this was associated with downregulation of 25OHD to 1,25(OH)(2) D metabolism, and concomitant suppression of intracrine induced 24-hydroxylase (CYP24A1) and antibacterial cathelicidin (LL37). FGF23 suppression of CYP27B1 was particularly pronounced in PBMCm treated with interleukin-15 to stimulate synthesis of 1,25(OH)(2) D. These data indicate that FGF23 can inhibit extra-renal expression of CYP27B1 and subsequent intracrine responses to 1,25(OH)(2) D in two different human monocyte models. Elevated expression of FGF23 may therefore play a crucial role in defining immune responses to vitamin D and this, in turn, may be a key determinant of infection in patients with chronic kidney disease (CKD).