Biochemical markers of iron status and iron accumulation in peritoneal dialysis patients treated with ferric citrate

BACKGROUND

Hyperphosphataemia is a common complication of kidney disease. Current dialysis techniques do not provide enough phosphorus clearance, hence the need to use phosphorus binders. Treatment options include calcium carbonate, calcium acetate, lanthanum carbonate, sevelamer hydrochloride and iron-based binders. Patients receiving peritoneal dialysis (PD) with sustained elevated ferritin levels exceeding 800 ng/mL are at a higher risk of death. We identify PD patients treated with iron-based binders and compare ferritin and risk of iron accumulation to patients treated with non-iron-based binders.

METHODS

All records of patients receiving PD at Emory dialysis centres until 30 October 2021 were reviewed for phosphorus binders. Basic demographics and laboratory data were time-referenced to the days on treatment with a particular binder. Patients were followed until discontinuation of the phosphorus binder, death, transplant, transfer to another dialysis provider or censoring at 36 months after medication was started.

RESULTS

Compared to calcium acetate and sevelamer, ferric citrate utilisation in PD patients resulted in a sustained increase in ferritin. The proportion of patients with a ferritin equal to or greater than 800 ng/dL and transferrin saturation greater than 40% increased over time in patients treated with ferric citrate and was higher during the second and third year of follow-up compared to baseline values and to patients treated with calcium acetate or sevelamer. Two patients (7%) treated with ferric citrate developed clinically significant haemosiderosis.

CONCLUSIONS

Use of ferric citrated in PD resulted in significant iron accumulation as judged by ferritin levels.

Autosomal Recessive Adolescent Syndromic Nephronophthisis Caused by a Novel Compound Heterozygous Pathogenic Variant

BACKGROUND Nephronophthisis, an autosomal recessive ciliopathy involving mutations in primary cilium genes, is characterized by chronic tubulointerstitial nephritis and a defective urine concentrating capacity. It accounts for about 5% of renal failure in children and adolescents and usually progresses to end-stage renal disease before the age of 30 years. Nephronophthisis is associated with extrarenal manifestations, including retinitis pigmentosa in Senior-Loken syndrome (SLS), and liver fibrosis in 10-20% of cases. While some presenting patterns could be characteristic, patients may have atypical presentation, making diagnosis difficult. Tubulointerstitial fibrosis is the predominant feature on histology and as such, diagnosis depends mostly on genetic testing. Despite advances in renal genomics over the years with a better understanding of primary cilia and ciliary theory, about 40% of nephronophthisis cases go undiagnosed. As the underlying genetic etiologies are not fully understood, morphologic pathologic findings are non-specific, and treatment options are limited to dialysis and transplantation. CASE REPORT We describe a unique case of a patient with adolescent nephronophthisis who presented with advanced chronic kidney disease and severe pancytopenia, who progressed to end-stage renal disease at the age of 19, and was found to have syndromic nephronophthisis with compound heterozygous inheritance. CONCLUSIONS This report highlights the atypical presentation patterns that can be seen in syndromic nephronophthisis, the importance of genetic diagnosis when there is a high index of suspicion, and the need to further study genetic variants to better understand and diagnose the disease and to develop targeted therapy.

Cushing's Syndrome Due to a Functional Thymic Neuroendocrine Tumor in Multiple Endocrine Neoplasia Type 1 Syndrome

Multiple endocrine neoplasia type 1 (MEN 1) syndrome is characterized by endocrinopathies and could be associated with thymic neuroendocrine tumors (NET). On rare occasions, they can be functional adrenocorticotropic hormone-secreting thymic carcinoid leading to Cushing's syndrome. In this report, we describe a case of adrenocorticotropic hormone (ACTH)-dependent Cushing's syndrome due to a thymic NET associated with MEN type 1 syndrome. We highlight its aggressive clinical course, the premise for a high index of suspicion for an ectopic ACTH secretion, and the need for early surgical resection combined with medical therapy and alternative treatments.

Double valve involvement: papillary fibroelastoma in a patient with severe mitral and aortic valve regurgitation

Cardiac papillary fibroelastoma is a benign neoplasm that arises in the endocardium. It commonly presents as an incidental finding on transthoracic echocardiography or as emboli to the coronary, cerebral or pulmonary vasculature. Clinical manifestations described in the literature have generally been related to a sequelae of the associated embolic phenomenon of these lesions. Valve regurgitation is less common with papillary fibroelastoma and when found, it is not known to cause severe regurgitation requiring valve replacement. We report a case of papillary fibroelastoma in a patient with severe mitral and aortic valve regurgitation in association with mobile masses requiring double valve replacement. This patient managed initially as infective endocarditis with severe double valve regurgitation, was found to have valvular masses concernng for papillary fibroelastoma and subsequently confirmed on pathology.

Cryoglobulinemic Vasculitis Masquerading as Bilateral Carpal Tunnel Syndrome

Cryoglobulinemic vasculitis (CV) is a systemic inflammatory syndrome involving small- to medium-sized vessels. Almost half of hepatitis C-infected patients have detectable cryoglobulins levels, but only very few develop clinical manifestations. In this case report, we bring forth a diagnostic challenge of CV. A 52-year-old man with untreated hepatitis C (high viral load), diabetes mellitus, hypertension, and chronic kidney disease 4 (CKD) with solitary left kidney presented with one month of bilateral hand pain that started in his right hand, progressed to involve the left with numbness more on the palmer aspects and lateral three fingers. Physical exam was significant for bilateral positive Phalen and Tinel's sign. CV occurs due to precipitation of immune complexes within the vessels. Palpable purpura, arthralgia, and weakness have been described as the core symptoms of CV. However, progressive acute to subacute neuropathy, especially bilateral, should raise concerns for vasculitic neuropathy.

A rare case of generalized tonic-clonic seizure related to paclitaxel infusion

WHAT IS KNOWN AND OBJECTIVE

Paclitaxel (Taxol) is an antineoplastic agent approved in the United States for the treatment of lung, breast, cervical, pancreatic cancers and Kaposi sarcoma. Paclitaxel does not cross the blood brain barrier, so central nervous system adverse effects are uncommon.

CASE DESCRIPTION

We describe a 60-year-old woman with Stage IIIa squamous cell carcinoma of the left lung, who developed a generalized tonic-clonic seizure during her first infusion of paclitaxel.

WHAT IS NEW AND CONCLUSION

Seizure related to a hypersensitivity reaction from paclitaxel infusion are rare but could be life-threatening and require immediate recognition, treatment and exclusion of other possible aetiologies.

Nitrous Oxide-induced B12 Deficiency Presenting With Myeloneuropathy

Nitrous oxide abuse is an uncommon cause of subacute combined degeneration of the spinal cord. This is a case of a 27-year-old female exotic dancer who presented with clinical and laboratory manifestations of subacute combined degeneration of the spinal cord secondary to nitrous oxide-induced B12 deficiency from chronic whippets consumption.

Association between cannabis use and complications related to ulcerative colitis in hospitalized patients: A propensity matched retrospective cohort study

Ulcerative colitis (UC) is a chronic inflammatory process that is occasionally associated with complications that cause significant morbidity and mortality. Studies in experimental animal models have demonstrated a beneficial effect of cannabis on intestinal inflammation. It is however unknown if this corresponds to fewer complications for patients with Ulcerative Colitis.We aimed to compare the prevalence of UC related complications and certain key clinical endpoints among cannabis users and nonusers hospitalized with a primary diagnosis of UC, or primary diagnosis of a UC-related complication with a secondary diagnosis of UC.Using data from the Healthcare Cost and Utilization Project-National Inpatient Sample (NIS) during 2010-2014, a total of 298 cannabis users with UC were compared to a propensity score matched group of nonusers with UC. We evaluated several UC-related complications and clinical endpoints.Within our matched cohort, prevalence of partial or total colectomy was lower in cannabis users compared to nonusers (4.4% vs 9.7%, P = .010) and there was a trend toward a lower prevalence of bowel obstruction (6.4% vs 10.7%, P = .057). Cannabis users had shorter hospital length-of-stay (4.5 vs 5.7 days P < .007) compared to their nonuser counterparts.Cannabis use may mitigate some of the well described complications of UC among hospitalized patients. Our findings need further evaluation, ideally through more rigorous clinical trials.

Atypical presentation of necrotising autoimmune myopathy

Necrotising autoimmune myopathy (NAM) is characterised by a common phenotype of profound symmetrical proximal muscle weakness, elevated creatine kinase levels, irritable myopathy on electromyography and histological findings of myocyte necrosis and regeneration without remarkable inflammation. NAM is associated with autoimmune antibodies including anti-3-hydroxy-3-methylglutaryl-coenzyme receptor, which is strongly associated with statin use. We report a case of statin-associated NAM with an atypical presentation of severe oropharyngeal dysphagia and no remarkable proximal muscle weakness at initial presentation but with rapid progression to severe quadriparesis in weeks. This case expands the spectrum of presentation patterns of this rare disease and highlights the need for a high index of suspicion in patients with a remote history of statin use.

A Unique Case of Drug Interaction between Ticagrelor and Statin Leading to Acute Renal Failure

Dual antiplatelet agents and high-intensity statins are frequently used in combination after myocardial infarction. Ticagrelor has the potential of causing acute kidney injury. Rosuvastatin is excreted through the kidneys and dose adjustment is needed in patients with kidney disease. When used in combination, they can potentiate the toxic effects of each other. We report a case of drug interaction between rosuvastatin and ticagrelor resulting in rhabdomyolysis and acute renal failure necessitating dialysis. This case stresses the importance of monitoring renal function and adjusting the dose of rosuvastatin accordingly in patients with kidney disease.