Rituximab-induced mild encephalopathy with a reversible splenial lesion syndrome (MERS): An adverse effect to add to the list.

Mild encephalopathy with a reversible splenial lesion syndrome (MERS) is a rare clinico-radiological entity. Rituximab (RTX)-induced MERS has never been described before. Herein, we report the case of a 33-year-old patient diagnosed since 2017, with an IgG4-related disease (IgG4-RD). This diagnosis was retained in the face of a prolonged fever, sicca syndrome, hepatic damage and renal pseudotumour associated to a high level of IGg4 at 2.8 g/L with suggestive renal histology. The patient was treated with corticosteroid therapy with persistence of renal impairment and nephrotic syndrome indicating RTX therapy. The patient received his first dose of RTX and presented neurological and respiratory impairments a few hours afterwards. An infectious investigation comprising a SARS CoV-2 PCR and viral PCRs (VZV, herpes and CMV) on cerebrospinal fluid (CSF) were negative. The HBV, HCV, HIV, Parvo B19, CMV, EBV, herpes, mycoplasma and syphilis serologies as well as Legionella antigenuria were also negative. The patient had received intravenous immunoglobulins (IVIG) and methylprednisone, associated with sodium valproate with favourable outcome. The diagnosis of MERS induced by RTX was retained in our patient according to clinical and radiological features. We herein report the first case of MERS following RTX in a patient treated for IgG4-RD.

Pristinamycin-induced toxic epidermal necrolysis: A case report.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are acute, life-threatening and rare severe cutaneous adverse reactions induced by drugs in most cases. The drugs most often reported to be implicated in inducing TEN/SJS are allopurinol, antibacterial sulfonamides, antiepileptic drugs and oxicam. Pristinamycin is an oral streptogramin antibiotic with bactericidal activity against Gram-positive bacteria that is rarely linked to TEN. Typically, this condition develops 4-28 days after drug exposure, Herein, we report a case of a 71-year-old female who developed TEN within 3 days of administration of pristinamycin and was managed successfully with supportive care, including intravenous fluids, pain control, prophylactic antibiotics and intravenous methylprednisolone. This case of rapidly developing SJS/TEN after administration of pristinamycin highlights the possibility that these complications can develop within only a few days following ingestion of drugs thought to be probably safe.

Glutathione S-transferase M1 and T1 polymorphisms and the risk of mild hepatotoxicity induced by carbamazepine in a tunisian population study.

BACKGROUND: The aim of this study was to evaluate whether the glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) null alleles may contribute to carbamazepine-induced hepatotoxicity. METHODS: A cross-sectional prospective study was conducted to identify the frequency distribution of GSTM1 and GSTT1 alleles in 129 Tunisian epileptic patients treated with carbamazepine. Null alleles were determined using a Polymerase Chain Reaction. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured by standard methods. RESULTS: Our results showed that the frequencies of GSTM1 (-) null allele and GSTT1 null (-) allele were 74.4 and 17.8% respectively. The ALT and AST levels were elevated in 46 (35.7%) and 33 (25.6%) cases. The mean values of ALT and AST were approximately 1.32 and 3.61 times higher than the upper limit of normal levels, respectively. The values of ALT and AST were significantly higher in GSTM1 (-) allele than in GSTM1 (+) (p = 10-3.and 0.004, respectively). The level of ALT was significantly higher in combination of GSTM1 (-)/T1(-) than in combined GSTM1(-)/T1(+) and combined GSTM1(+)/T1(+) (p = 0.2 and 0.03, respectively), and that of AST was significantly higher in combination of GSTM1(-)/T1(-) and in combination of GSTM1(+)/T1(-) than in combination of GSTM1(+)/T1(+) (p = 10-3 and 10-3, respectively). CONCLUSIONS: Our findings suggest that the GSTM1 (-) allele may be considered as a key factor for the development of carbamazepine-induced hepatotoxicity. Results related to GSTT (-) allele and elevation in AST levels should be considered with caution as AST may be elevated in other pathophysiological conditions.

Drug-induced hyperuricaemia and gout.

Hyperuricaemia is a common clinical condition that can be defined as a serum uric acid level >6.8 mg/dl (404 µmol/l). Gout, a recognized complication of hyperuricaemia, is the most common inflammatory arthritis in adults. Drug-induced hyperuricaemia and gout present an emergent and increasingly prevalent problem in clinical practice. Diuretics are one of the most important causes of secondary hyperuricaemia. Drugs raise serum uric acid level by an increase of uric acid reabsorption and/or decrease in uric acid secretion. Several drugs may also increase uric acid production. In this review, drugs leading to hyperuricaemia are summarized with regard to their mechanism of action and clinical significance. Increased awareness of drugs that can induce hyperuricaemia and gout, and monitoring and prevention are key elements for reducing the morbidity related to drug-induced hyperuricaemia and gout.

Effects of EPHX1 and CYP3A4*22 genetic polymorphisms on carbamazepine metabolism and drug response among Tunisian epileptic patients.

The aim of this study was to evaluate the impact of polymorphisms in the EPHX1 (c.416A > G, c.337T > C) and CYP3A4*22 genes involved in carbamazepine (CBZ) metabolism and pharmacoresistance among 118 Tunisian patients with epilepsy under maintenance dose of CBZ. These genetic polymorphisms were analyzed by PCR-RFLP. Associations between plasma CBZ concentration, CBZ-E concentration, maintenance doses and metabolic ratio (CBZ-E:CBZ, CBZ-D:CBZ-E) were analyzed with each polymorphism. Both variants of EPHX1 c.416A > G and c.337T > C are significantly associated with higher metabolic ratio CBZ-E:CBZ and seem to decrease the activity of the epoxide hydrolase. The CYP3A4*22 variant allele is significantly associated with lower CBZ-D:CBZ-E ratio and seems also to be associated with less activity of the cytochrome. Our data suggest that certain polymorphisms of metabolizing enzyme genes could influence inter-individual variability of CBZ metabolism.

[Not Available]. / Vascularite cutanée leucocytoclasique induite par la gabapentine.

We describe the case of a woman who developped a cutaneous leukocytoclastic vasculitis following a treatement with gabapentine.

[Gabapentin-induced cutaneous leukocytoclastic vasculitis]. / Vascularite cutanée leucocytoclasique induite par la gabapentine.

We describe the case of a woman who developed a cutaneous leukocytoclastic vasculitis following a treatment with gabapentine.

Effect of Zinc Oxide Nanoparticles on Liver Functions in Albino Mice.

BACKGROUND: An alarming number of zinc oxide nanoparticles (ZnO-NPs) have leaked into the environment, endangering the tissues of many living creatures, due to the recent surge in their use in several items. Through intra-peritoneal injection, this research intends to examine the impact of ZnO-NPs on the hepatic and gastrointestinal structures of male albino mice. METHOD: For seven and 14 days, animals were given 0.1 ml of 100 and 200 mg kg-1 of 50 nm-size ZnO-NPs, respectively. In contrast, those in the control group were given only water and food. RESULT: The results demonstrated that the treated mice's livers underwent functional changes and histological damage. After seven and 14 days, there was a notable rise in the average levels of the glutamate-oxaloacetate transaminase and glutamate-pyruvate transaminase enzymes in comparison to the control group (p≤0.05). Concentration time determines the magnitude of this impact. When enzyme levels vary, it means the liver isn't working properly. Histological changes in the liver, such as necrosis, destruction of hepatocyte membranes, widening of sinusoidal spaces and vacuolation of their cytoplasm, vascular congestion, and an increased number of Kupffer cells, were induced in mice treated with ZnO-NPs at two studied concentrations (100 and 200 mg/kg) for seven and 14 days, respectively. These effects were time-dose-dependent, according to the results of hematoxylin-eosin staining of liver tissue images.

Drug-Induced Hypouricemia.

Hypouricemia is defined as a serum uric acid concentration of ≤ 2.0 mg/dL or 119 µmol/L. Hypouricemia may occur secondarily to a number of underlying conditions, including severe hepatocellular disease, neoplasia, defective renal tubular reabsorption of uric acid, inherited metabolic defect in purine metabolism, and drugs. Medications are an important cause of hypouricemia. They can cause hypouricemia by a variety of mechanisms. Drug-induced hypouricemia mostly occurs as overtreatment of hyperuricemia by urate-lowering therapies including xanthine oxidase inhibitors, uricosuric agents and uricases. Drugs not used in the treatment of gout may also lead to a decrease of uric acid levels. In this literature review, medications leading to hypouricemia are summarized with regard to their mechanism of action and clinical significance.

Acute generalized exanthematous pustulosis: Analysis of cases managed in a Tunisian tertiary hospital.

Acute generalized exanthematous pustulosis (AGEP) is a severe and life-threatening cutaneous adverse reaction. Drug-induced AGEP is mainly related to antibiotics. More recently, AGEP following spider bites has been increasingly described. Treatment includes withdrawal of the offending drug and supportive care. In Tunisia, data concerning severe cutaneous adverse reactions (SCARs) in general and especially AGEP is lacking. Herein, we conducted a retrospective study to investigate the epidemiological, clinical characteristics and etiologies of AGEP referred to the Dermatology department. Our study included 32 cases of AGEP. AGEP cases occurred in overall 8.9% of all SCARs referred to the department during the same period study. The majority were females (24 women and 7 men). The median age of the patients was 33 years. A history of psoriasis was reported in 16.1% of patients. All patients presented with an extensive erythematous rash with pinhead pustules. Neutrophil hyperleukocytosis (greater than 7000/mm3) was noted in 17 patients (63% of cases). It was associated with hypereosinophilia exceeding 500 elements/mm3 in 8 cases (29.6%). Drug-induced AGEP was reported in 53% of cases. Antibiotics were implicated in the majority of cases. Delay in onset ranged from 15hours to 7 days, with an average of 2.8 days. A non-drug-induced etiology was considered if the pharmacological investigation was negative, or if a clear non-drug trigger was found. It was retained in ten cases (48.4% of all observations). Spider bites were revealed in 8 cases. AGEP represents a severe, usually drug-related skin reaction. It is classified as a type IVd reaction mediating T cell-related sterile neutrophilic inflammatory response. It typically occurs within 24-48 h of ingestion of the offending drug. Antibiotics are the most common drug family to cause AGEP. Spider bites were involved in 25.8% of cases in our study, as important as antibiotic-induced AGEP. Analysis of the particularities of AGEP according to etiology, whether drug-induced or not, revealed the presence of an initial escarotic lesion (P=0.01) and the finding of blood hypereosinophilia (P=0.014) in the non-drug AGEP group were the distinguishing features. Blood hyperesoniophilia, more frequent in the non-drug AGEP group, suggests a pathophysiology probably different from that of the drug AGEP group. Clinicians should be aware of both etiologies. Our study focuses on the importance of AGEP associated with spider bite as a potential triggering factor in Tunisia.