Update on heme biosynthesis, tissue-specific regulation, heme transport, relation to iron metabolism and cellular energy.

Heme is a primordial macrocycle upon which most aerobic life on Earth depends. It is essential to the survival and health of nearly all cells, functioning as a prosthetic group for oxygen-carrying proteins and enzymes involved in oxidation/reduction and electron transport reactions. Heme is essential for the function of numerous hemoproteins and has numerous other roles in the biochemistry of life.

Drug-Induced Liver Injury in Pregnancy: The U.S. Drug-Induced Liver Injury Network Experience.

There are limited data on the causative agents and characteristics of drug-induced liver injury in pregnant individuals. Data from patients with drug-induced liver injury enrolled in the ongoing multicenter Drug-Induced Liver Injury Network between 2004 and 2022 and occurring during pregnancy or 6 months postpartum were reviewed and compared with cases of drug-induced liver injury in nonpregnant women of childbearing age. Among 325 individuals of childbearing age in the Drug-Induced Liver Injury Network, 16 cases of drug-induced liver injury (5%) occurred during pregnancy or postpartum.

Drug-induced liver injury (DILI) ascribed to non-steroidal anti-inflammatory drugs (NSAIDs) in the USA-Update with genetic correlations.

Objective: To describe patients with NSAID-DILI, including genetic factors associated with idiosyncratic DILI.

Methods: In DILIN, subjects with presumed DILI are enrolled and followed for at least 6 months. Causality is adjudicated by a Delphic approach.

Obstacles to Early Diagnosis of Acute Hepatic Porphyria: Current Perspectives on Improving Early Diagnosis and Clinical Management.

Porphyrias are, for the most part, inherited disorders of the heme biosynthetic pathway which lead to accumulation of specific intermediates responsible for most of the symptoms and signs of biochemically active disease. Acute hepatic porphyrias usually come to clinical attention primarily in women in their reproductive years who present with episodic, severe, generalized abdominal pain. Such acute attacks may also be associated with tachycardia, systemic arterial hypertension, hyponatremia, recent history of dark reddish to brownish urine, and anxiety, delirium, and sensory or motor neuropathies.

Efficacy and safety of givosiran for acute hepatic porphyria: Final results of the randomized phase III ENVISION trial.

Background & Aims: Acute hepatic porphyria (AHP) is caused by defects in hepatic heme biosynthesis, leading to disabling acute neurovisceral attacks and chronic symptoms. In ENVISION (NCT03338816), givosiran treatment for 6 months reduced attacks and other disease manifestations compared with placebo. Herein, we report data from the 36-month final analysis of ENVISION.

When Is Suspected Drug-Induced Liver Injury (DILI) Not DILI? An Analysis of Unlikely Cases From the Drug-Induced Liver Injury Network.

Introduction: Diagnosis of drug-induced liver injury (DILI) is difficult. We reviewed cases in the DILI Network prospective study that were adjudicated to have liver injury due to other causes to discover pearls for improved diagnostic accuracy.

Methods: Cases were adjudicated by expert opinion and scored from 1 (definite DILI) to 5 (unlikely DILI).

Dersimelagon in Erythropoietic Protoporphyrias.

Background: Erythropoietic protoporphyria and X-linked protoporphyria are inborn errors of heme biosynthesis that cause elevated circulating levels of metal-free protoporphyrin and phototoxicity. Both disorders are characterized by excruciating phototoxic attacks after exposure to visible light. Dersimelagon is a new, orally administered, selective melanocortin 1 receptor agonist that increases levels of skin eumelanin.

Recurrent symptoms of acute intermittent porphyria after biochemical normalization with givosiran-An ongoing clinical conundrum.

A 47-year-old woman with acute intermittent porphyria (AIP) has had recurring symptoms after achieving biochemical normalization of her urinary 5-aminolevulinic acid (ALA), porphobilinogen (PBG), and total porphyrins with givosiran. She has had normal liver tests, mildly decreased renal function, and sustained normal urinary ALA, PBG, and porphyrins with no rebound in her laboratory test results throughout treatment. She continues to tolerate monthly givosiran injections with no adverse effects, but she still experiences what she believes are acute porphyric attacks every 1-2 months.

The Impact of Patient Age and Corticosteroids in Patients With Sulfonamide Hepatotoxicity.

Introduction: Sulfonamides are widely used to treat and prevent various bacterial and opportunistic infections. The aim of this study was to describe the clinical presentation and outcomes of a large cohort of patients with sulfonamide hepatotoxicity.

Methods: Between 2004 and 2020, 105 patients with hepatotoxicity attributed to trimethoprim/sulfamethoxazole (TMP-SMZ) (n = 93) or other sulfonamides (n = 12) were enrolled.

Ledipasvir/Sofosbuvir Is Effective as Sole Treatment of Porphyria Cutanea Tarda with Chronic Hepatitis C.

Background And Aims: Chronic hepatitis C [CHC] is a risk factor for porphyria cutanea tarda [PCT]. To assess whether ledipasvir/sofosbuvir is effective for treating both PCT and CHC, we treated patients with CHC + PCT solely with ledipasvir/sofosbuvir and followed them for at least 1 year to assess cure of CHC and remission of PCT.

Methods: Between September 2017 and May 2020, 15 of 23 screened PCT + CHC patients were eligible and enrolled.

Idiosyncratic drug-induced liver injury caused by givosiran in a patient with acute intermittent porphyria.

A 39-year-old woman with biochemically and clinically active acute intermittent porphyria (AIP) developed moderately severe liver injury after receiving her second dose of givosiran. Serologic evaluation ruled out hepatitis caused by viral, autoimmune, or other metabolic etiologies. The updated Roussel Uclaf Causality Assessment Method (RUCAM) score was 8 and the Revised Electronic Causality Assessment Method (RECAM) score for givosiran was 9.

A pilot study of oral iron therapy in erythropoietic protoporphyria and X-linked protoporphyria.

The use of iron supplementation for anemia in erythropoietic protoporphyria (EPP) is controversial with both benefit and deterioration reported in single case reports. There is no systematic study to evaluate the benefits or risks of iron supplementation in these patients. We assessed the potential efficacy of oral iron therapy in decreasing erythrocyte protoporphyrin (ePPIX) levels in patients with EPP or X-linked protoporphyria (XLP) and low ferritin in an open-label, single-arm, interventional study.

Liver Injury Associated with Turmeric-A Growing Problem: Ten Cases from the Drug-Induced Liver Injury Network [DILIN].

Background: Turmeric is a commonly used herbal product that has been implicated in causing liver injury. The aim of this case series is to describe the clinical, histologic, and human leukocyte antigen (HLA) associations of turmeric-associated liver injury cases enrolled the in US Drug-Induced Liver Injury Network (DILIN).

Methods: All adjudicated cases enrolled in DILIN between 2004 and 2022 in which turmeric was an implicated product were reviewed.

Clinical features, outcomes, and HLA risk factors associated with nitrofurantoin-induced liver injury.

Background & Aims: Nitrofurantoin (NTF) is widely used for the treatment (short-term) and prevention (long-term) of urinary tract infections. We aimed to describe the clinical characteristics, outcomes, and HLA risk factors for NTF-induced liver injury (NTF-DILI) among individuals enrolled in the Drug Induced Liver Injury Network (DILIN).

Methods: Seventy-eight individuals with definite, highly likely, or probable NTF-DILI were enrolled into DILIN studies between 2004-2020.

Eslicarbazepine acetate is porphyrogenic and should be used with caution in patients with the acute hepatic porphyrias.

Eslicarbazepine acetate, a third-generation antiepileptic drug (AED), has shown improved clinical response and safety in comparison to older generation AEDs for patients with partial-onset seizures. It is currently not known whether eslicarbazepine acetate is safe to use in patients with the acute hepatic porphyrias (AHPs) since a few first-generation AEDs, such as phenobarbital and carbamazepine, are known porphyrogenic agents. In this study, we used a recently published fluorescence-based screening assay to screen for porphyrogenicity in various agents.

Elagolix is porphyrogenic and may induce porphyric attacks in patients with the acute hepatic porphyrias.

Elagolix is an FDA-approved treatment for moderate-to-severe pain associated with endometriosis but has been associated with increased acute porphyric attacks in women with the acute hepatic porphyrias (AHPs). A fluorescence-based screening assay for drug porphyrogenicity in LMH cells indicates that elagolix is porphyrogenic; thus, elagolix should be avoided or used with caution in patients with the AHPs.

EXPLORE B: A prospective, long-term natural history study of patients with acute hepatic porphyria with chronic symptoms.

One-year data from EXPLORE Part A showed high disease burden and impaired quality of life (QOL) in patients with acute hepatic porphyria (AHP) with recurrent attacks. We report baseline data of patients who enrolled in EXPLORE Part B for up to an additional 3 years of follow-up. EXPLORE B is a long-term, prospective study evaluating disease activity, pain intensity, and QOL in patients with AHP with ≥1 attack in the 12 months before enrollment or receiving hemin or gonadotropin-releasing hormone prophylaxis.