HIV-infected patients have a higher risk of developing cutaneous reactions than the general population, which has a significant impact on patients’ current and future care options. The severity of cutaneous adverse reactions varies greatly, and some may be difficult to manage. HIV-infected patients just at the beginning of antiretroviral treatment can frequently show a wide variety of adverse drug effects such as drug rashes, hyperpigmentation, hair loss, hypersensitivity reactions, injection site reaction, urticarial reaction, erythema multiforme, toxic epidermal necrolysis or Stevens–Johnson syndrome. The early detection and treatment of cutaneous adverse drug reactions, plus identification of the causative agent, are essential to prevent the progression of the reaction, preventing additional exposures and ensuring the appropriate use of medications for the current condition and keeping in mind others, such as patient age. This article emphasizes the most common features of an antiretroviral drug-induced cutaneous reaction from protease inhibitors, non-nucleoside analogue reverse transcriptase inhibitors, fusion inhibitors, nucleoside reverse transcriptase inhibitors, integrase inhibitors and inhibitors of the CCR5 chemokine receptor, paying special attention to the newest drugs approved for the treatment of HIV infection, such as tipranavir, darunavir, etravirine, enfuvirtide, raltegravir and maraviroc.

OBJECTIVE: To report a probable interaction between meropenem and valproic acid that resulted in the development of epileptic seizures. CASE SUMMARY: A 21-year-old woman presented to our emergency department because of a new-onset, generalized tonic—clonic seizure and was admitted to the intensive care unit. Treatment with valproic acid 1000 mg as a continuous intravenous infusion over 24 hours was initiated. On day 6, the serum concentration of valproic acid was 52.5 μg/mL. On day 13, treatment with intravenous meropenem 1 g 3 times daily was started. On day 15, when the patient was afebrile, numerous myoclonic episodes occurred involving her arms and face; the serum concentration of valproic acid at that time was 42 μg/mL. The valproic acid dose was increased to 2880 mg. Two days later, a generalized tonic—clonic seizure occurred despite the increased dosage, and the plasma concentration of valproic acid fell to 7 μg/mL. The valproic acid dose was increased the following day to 3600 mg; however, the serum concentrations remained <10 μg/mL. On day 19, based on the results of a blood culture and the suspicion of an interaction between meropenem and valproic acid, meropenem therapy was suspended. The serum concentration of valproic acid was 52.4 μg/mL on day 27. Three days later, the patient was asymptomatic and was discharged. DISCUSSION: Coadministration of valproic acid and other drugs that are metabolized by the hepatic cytochrome P450 isoenzyme system can lead to clinically relevant interactions by induction or inhibition of enzymes in shared metabolic pathways. In view of studies in experimental models, the interaction between carbapenem antibiotics and valproic acid is at least possible. Use of the Naranjo probability scale indicated a probable relationship between acute seizures and a meropenem—valproic acid interaction in this patient. CONCLUSIONS: This case report provides strong evidence for an interaction between valproic acid and meropenem. Clinicians should be aware of this potential interaction that may be associated with a serious adverse effect as the result of the decrease of the valproic acid serum concentrations.

Objective:To review adverse cutaneous drug reactions induced by tumor necrosis factor alpha (TNF-&agr;) antagonist therapy.Methods:A literature search was performed using PubMed (1996–March 2009), EMBASE, and selected MEDLINE Ovid bibliography searches. All language clinical trial data, case reports, letters, and review articles identified from the data sources were used.Results:Since the...

The objective was using the Essential Medicines List for children by the World Health Organization (WHO) to create a pediatric biopharmaceutics classification system (pBCS) of the oral drugs included in the Essential Medicines List by the World Health Organization and to compare our results with the BCS for adults (aBCS). Several methods to estimate the oral drug dose in different pediatric groups were used to calculate dose number (Do) and solubility (high/low). The estimation of the gastrointestinal water volume was adapted to each pediatric group. Provisional permeability classification was done by comparison of each drug lipophilicity versus metoprolol as the model drug of high permeability. As a result, 24.5% of the included drugs moved from the favorable to unfavorable class (i.e., from high to low solubility). Observed changes point out potential differences in product performance in pediatrics compared to adults, due to changes in the limiting factors for absorption. BCS Class Changes 1 to 2 or 3 to 4 are indicative of drugs that could be more sensitive to the choice of appropriate excipient in the development process. Validating a pBCS for each age group would provide a valuable tool to apply in specific pediatric formulation design by reducing time and costs and avoiding unnecessary pediatric experiments restricted due to ethical reasons. Additionally, pBCS could minimize the associated risks to the use of adult medicines or pharmaceutical compound formulations.

To report a case of Henoch-Schönlein purpura that appears to be related to the intake of clarithromycin for pharyngitis/tonsillitis. We describe a case of Henoch-Schönlein associated with clarithromycin therapy in a 48-year-old white man with no history of allergic drug reactions. Four days after starting therapy, he came to our hospital emergency room because of a non-pruritic palpable purpuric rash on the trunk and extremities and arthralgias involving elbows and knees. Administration of clarithromycin was suspended, in a few days, arthralgias and skin lesions quickly resolved. Three weeks later, the patient presented again with abdominal pain, dark-red urine and swelling of the legs. Urinalysis revealed proteinuria of 11 g/24 h and hematuria. A percutaneous renal biopsy showed a diffuse endocapillary proliferative glomerulonephritis with segmental areas of fibrinoid necrosis within glomeruli, on immunofluorescence study granular deposits of IgA and C3 were present in the mesangium and capillary walls. A diagnosis of HSP was made. We suspected that the causative agent might be clarithromycin since this was the only drug added before the cutaneous and renal condition appeared. Our case and the previous case suggest that HSP may represent a potential adverse effect of clarithromycin, clinicians should be alerted to this potentially severe side effect of such a widely used drug. In accordance with the data obtained and based on the Naranjo algorithm, the adverse reaction could be considered possible.

OBJECTIVE: To report a case of optic neuritis associated with concurrent etanercept and isoniazid therapy. CASE SUMMARY: A 55-year-old man diagnosed as having rheumatoid arthritis had received treatment with nonsteroidal anti-inflammatory drugs, sulfasalazine, oral methotrexate, leflunomide, and deflazacort. Four months prior to admission, he had a Disease Activity Score of 6.06; treatment with etanercept was considered. Three months prior to admission, because of evidence of latent tuberculosis, isoniazid 300 mg once daily and pyridoxine 50 mg once daily were prescribed. Treatment with subcutaneous etanercept 25 mg twice weekly was started 5 days after isoniazid was initiated. Two weeks prior to admission, the patient developed blurred vision in his left eye. Ten days later, his vision worsened and he was hospitalized. The visual acuity in both eyes was 0.7, and a campimetric examination was compatible with optic neuritis. Magnetic resonance imaging of the brain revealed lesions suggesting demyelinating lesions. The clinical course was consistent with bilateral optic neuritis. Etanercept was stopped, and isoniazid was replaced with rifampin 600 mg once daily. The patient was treated with intravenous methylprednisolone hemisuccinate 1 g/day for 5 days followed by oral prednisolone, resulting in a minor subjective improvement in left eye visual acuity. He then received oral prednisone for 3 weeks, slowly tapering to discontinuation. DISCUSSION: No physiologic factors could have predisposed this patient to develop optic neuritis. He was not diagnosed with a demyelinating disease or underlying systemic condition. The optic neuritis was unlikely to be an early manifestation of multiple sclerosis based on the clinical course and the negative results of the imaging tests. Furthermore, there was a close temporal correlation between the drug exposure and the onset of symptoms. After discontinuation of etanercept and isoniazid therapy, the patient's general condition improved. Use of the Naranjo probability scale indicated a possible relationship between optic neuritis and combined etanercept–isoniazid therapy. CONCLUSIONS: Patients initiated on etanercept and isoniazid should be closely monitored for the development of adverse neurologic signs and effects. If optic neuritis is determined, etanercept and isoniazid should be discontinued immediately.