Fatal Stevens-Johnson syndrome in an AIDS patient treated with sulfadiazine

Toxoplasmic maculopathy with bacillary layer detachment in a pediatric patient

We report the case of a 14-year-old girl with ocular toxoplasmosis presenting with severe panuveitis with anterior segment involvement, moderate vitreous haze, focal retinochoroiditis, extensive retinal periphlebitis, and macular bacillary layer detachment. Toxoplasmosis treatment was complicated by Stevens-Johnson syndrome, which developed 8 days after starting trimethoprim-sulfamethoxazole.

Suppressors for Human Epidermal Growth Factor Receptor 2/4 (HER2/4): A New Family of Anti-Toxoplasmic Agents in ARPE-19 Cells

The effects of tyrosine kinase inhibitors (TKIs) were evaluated on growth inhibition of intracellular Toxoplasma gondii in host ARPE-19 cells. The number of tachyzoites per parasitophorous vacuolar membrane (PVM) was counted after treatment with TKIs. T. gondii protein expression was assessed by western blot. Immunofluorescence assay was performed using Programmed Cell Death 4 (PDCD4) and T. gondii GRA3 antibodies. The TKIs were divided into 3 groups; non-epidermal growth factor receptor (non-EGFR), anti-human EGFR 2 (anti-HER2), and anti-HER2/4 TKIs, respectively. Group I TKIs (nintedanib, AZD9291, and sunitinib) were unable to inhibit proliferation without destroying host cells. Group II TKIs (lapatinib, gefitinib, erlotinib, and AG1478) inhibited proliferation up to 98% equivalent to control pyrimethamine (5 μM) at 20 μM and higher, without affecting host cells. Group III TKIs (neratinib, dacomitinib, afatinib, and pelitinib) inhibited proliferation up to 98% equivalent to pyrimethamine at 1–5 μM, but host cells were destroyed at 10–20 μM. In Group I, TgHSP90 and SAG1 inhibitions were weak, and GRA3 expression was moderately inhibited. In Group II, TgHSP90 and SAG1 expressions seemed to be slightly enhanced, while GRA3 showed none to mild inhibition; however, AG1478 inhibited all proteins moderately. Protein expression was blocked in Group III, comparable to pyrimethamine. PDCD4 and GRA3 were well localized inside the nuclei in Group I, mildly disrupted in Group II, and were completely disrupted in Group III. This study suggests the possibility of a vital T. gondii TK having potential HER2/4 properties, thus anti-HER2/4 TKIs may inhibit intracellular parasite proliferation with minimal adverse effects on host cells.

Afatinib Reduces STAT6 Signaling of Host ARPE-19 Cells Infected with Toxoplasma gondii

Specific gene expressions of host cells by spontaneous STAT6 phosphorylation are major strategy for the survival of intracellular Toxoplasma gondii against parasiticidal events through STAT1 phosphorylation by infection provoked IFN-γ. We determined the effects of small molecules of tyrosine kinase inhibitors (TKIs) on the growth of T. gondii and on the relationship with STAT1 and STAT6 phosphorylation in ARPE-19 cells. We counted the number of T. gondii RH tachyzoites per parasitophorous vacuolar membrane (PVM) after treatment with TKIs at 12-hr intervals for 72 hr. The change of STAT6 phosphorylation was assessed via western blot and immunofluorescence assay. Among the tested TKIs, Afatinib (pan ErbB/EGFR inhibitor, 5 µM) inhibited 98.0% of the growth of T. gondii, which was comparable to pyrimethamine (5 µM) at 96.9% and followed by Erlotinib (ErbB1/EGFR inhibitor, 20 µM) at 33.8% and Sunitinib (PDGFR or c-Kit inhibitor, 10 µM) at 21.3%. In the early stage of the infection (2, 4, and 8 hr after T. gondii challenge), Afatinib inhibited the phosphorylation of STAT6 in western blot and immunofluorescence assay. Both JAK1 and JAK3, the upper hierarchical kinases of cytokine signaling, were strongly phosphorylated at 2 hr and then disappeared entirely after 4 hr. Some TKIs, especially the EGFR inhibitors, might play an important role in the inhibition of intracellular replication of T. gondii through the inhibition of the direct phosphorylation of STAT6 by T. gondii.

Adverse cutaneous reactions to antimicrobials in patients with human immunodeficiency virus infection

Adverse reactions to medication are significant contributors to morbidity and mortality in patients with human immunodeficiency virus (HIV) infection. Cutaneous events not only constitute a significant portion of these reactions, they may also herald developing systemic reactions such as hemato-, nephro-, and hepatotoxicity. The identification of cutaneous adverse reactions and drug culprits and the proper management of reactions are of paramount importance for these patients. This review focuses specifically on adverse cutaneous reactions to antimicrobials that are commonly used in the management of patients with HIV infection.

Photo-induced Stevens-Johnson syndrome due to sulfasalazine therapy

OBJECTIVE

To report a case of photo-induced Stevens-Johnson Syndrome (SJS) due to sulfasalazine therapy.

CASE SUMMARY

Photo-induced SJS associated with sulfasalazine therapy occurred in a 34-year-old white man diagnosed as having seronegative symmetrical polyarthritis with no predisposing factors. According to his medical record, the patient had received methotrexate, levofolinate calcium, deflazacort, and diclofenac sodium as needed. Two months prior to admission, methotrexate and diclofenac sodium were suspended and treatment with sulfasalazine was started. The patient presented to our emergency department because of severe erythema confined to sun-exposed areas; annular lesions on the extremities and the mucosa were affected. Nikolsky's sign was present. A skin biopsy was compatible with SJS, and the clinical diagnosis was SJS induced by sulfasalazine. Administration of sulfasalazine was suspended, which resulted in an improvement in the skin lesions and general state of health. The patient was discharged without further symptoms.

DISCUSSION

The observed reaction to sulfasalazine was considered phototoxic, as lesions appeared like a burn rash reaction in sun-exposed areas when sulfasalazine treatment was started and the reaction progressed to SJS. It seems that there was a correlation between the time course of the reaction and the administration of sulfasalazine. An objective causality assessment revealed that the adverse effect was possible.

CONCLUSIONS

To our knowledge, this is the first report of photo-induced SJS due to sulfasalazine therapy. Clinicians should be aware of this infrequent but severe reaction. If clinical evaluation leads to the suspicion of SJS, sulfasalazine should be discontinued immediately.