Dapsone and sulfapyridine

Development of a multivariate predictive model for dapsone adverse drug events in people with leprosy under standard WHO multidrug therapy

BACKGROUND

The occurrence of adverse drug events (ADEs) during dapsone (DDS) treatment in patients with leprosy can constitute a significant barrier to the successful completion of the standardized therapeutic regimen for this disease. Well-known DDS-ADEs are hemolytic anemia, methemoglobinemia, hepatotoxicity, agranulocytosis, and hypersensitivity reactions. Identifying risk factors for ADEs before starting World Health Organization recommended standard multidrug therapy (WHO/MDT) can guide therapeutic planning for the patient. The objective of this study was to develop a predictive model for DDS-ADEs in patients with leprosy receiving standard WHO/MDT.

METHODOLOGY

This is a case-control study that involved the review of medical records of adult (≥18 years) patients registered at a Leprosy Reference Center in Rio de Janeiro, Brazil. The cohort included individuals that received standard WHO/MDT between January 2000 to December 2021. A prediction nomogram was developed by means of multivariable logistic regression (LR) using variables. The Hosmer-Lemeshow test was used to determine the model fit. Odds ratios (ORs) and their respective 95% confidence intervals (CIs) were estimated. The predictive ability of the LRM was assessed by the area under the receiver operating characteristic curve (AUC).

RESULTS

A total of 329 medical records were assessed, comprising 120 cases and 209 controls. Based on the final LRM analysis, female sex (OR = 3.61; 95% CI: 2.03-6.59), multibacillary classification (OR = 2.5; 95% CI: 1.39-4.66), and higher education level (completed primary education) (OR = 1.97; 95% CI: 1.14-3.47) were considered factors to predict ADEs that caused standard WHO/MDT discontinuation. The prediction model developed had an AUC of 0.7208, that is 72% capable of predicting DDS-ADEs.

CONCLUSION

We propose a clinical model that could become a helpful tool for physicians in predicting ADEs in DDS-treated leprosy patients.

Successful Treatment of Linear IgA Disease and Ulcerative Colitis With Sulfasalazine

Linear IgA disease (LAD) is an uncommon autoimmune blistering disease that has been associated with medications, malignancy, and other autoimmune diseases, such as ulcerative colitis (UC). In this case report, a patient with a history of UC developed characteristic LAD lesions. While dapsone is considered first-line therapy for LAD, the treatment team opted for an underutilized, plausibly less toxic, and more simplified treatment regimen with sulfasalazine, successfully utilizing the two distinct actions of sulfasalazine's components - sulfapyridine and 5-aminosalicylate (5-ASA) - to concurrently treat both the LAD and UC symptoms. The authors discuss the pathophysiology of LAD and UC and expound on the mechanistic theory of their association. Additionally, the pharmacodynamics of sulfasalazine and considerations of its side effect profile are examined.

Dapsone-induced methemoglobinemia and hemolysis in a woman without G6PD deficiency presenting with idiopathic urticaria

BACKGROUND

The appearance of bite cells associated with methemoglobinemia can be caused by oxidizing drugs such as dapsone in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency or high drug serum levels. Bite cells are often pathognomonic for oxidant injury in patients with G6PD deficiency and suggest active hemolysis.

CASE PRESENTATION

We report a case of a woman with no prior history of G6PD deficiency who presented with anemia, methemoglobinemia and bite cells on peripheral blood smear after dapsone therapy for new onset idiopathic urticaria. Laboratory tests for G6PD, blood count and liver function were within normal limits prior to initiation of therapy. During the patient's hospital course, moderate methemoglobinemia and anemia were identified despite mildly increased serum G6PD level. These pathologies were reversed upon stopping dapsone therapy.

CONCLUSION

This case highlights the potential for therapeutic levels of dapsone to induce side effects in patients without G6PD deficiency and highlights the importance of routine blood monitoring for anemia and hemolysis during the course of drug therapy.

Dapsone Azo-Linked with Two Mesalazine Moieties Is a "Me-Better" Alternative to Sulfasalazine

Dapsone (DpS) is an antimicrobial and antiprotozoal agent, especially used to treat leprosy. The drug shares a similar mode of action with sulfonamides. Additionally, it possesses anti-inflammatory activity, useful for treating autoimmune diseases. Here, we developed a “me-better” alternative to sulfasalazine (SSZ), a colon-specific prodrug of mesalazine (5-ASA) used as an anti-inflammatory bowel diseases drug; DpS azo-linked with two molecules of 5-ASA (AS-DpS-AS) was designed and synthesized, and its colon specificity and anti-colitic activity were evaluated. AS-DpS-AS was converted to DpS and the two molecules of 5-ASA (up to approximately 87% conversion) within 24 h after incubation in the cecal contents. Compared to SSZ, AS-DpS-AS showed greater efficiency in colonic drug delivery following oral gavage. Simultaneously, AS-DpS-AS substantially limited the systemic absorption of DpS. In a dinitrobenzene sulfonic acid-induced rat colitis model, oral AS-DpS-AS elicited better efficacy against rat colitis than oral SSZ. Moreover, intracolonic treatment with DpS and/or 5-ASA clearly showed that combined treatment with DpS and 5-ASA was more effective against rat colitis than the single treatment with either DpS or 5-ASA. These results suggest that AS-DpS-AS may be a “me-better” drug of SSZ with higher therapeutic efficacy, owing to the combined anti-colitic effects of 5-ASA and DpS.

S2k guidelines (consensus statement) for diagnosis and therapy of dermatitis herpetiformis initiated by the European Academy of Dermatology and Venereology (EADV)

INTRODUCTION

Dermatitis herpetiformis (DH) is a chronic, pruritic, gluten-induced skin disorder characterized by subepidermal granular IgA deposition and a variable degree of enteropathy identical to that seen in coeliac disease. So far, there has been no European consensus about the management of DH.

METHODS

The guidelines were created by small subgroups of a guideline committee consisting of 26 specialists from various medical fields and one patients' representative. The members of the committee then discussed the guidelines and voted for the final version at two consensus meetings. The guidelines were developed under the support of the European Academy of Dermatology and Venereology (EADV) and in collaboration with the European Dermatology Forum (EDF).

RESULTS

The guidelines summarize evidence-based and expert-based recommendations (S2 level) for the management of DH (see Appendix).

CONCLUSION

These guidelines will improve the quality of management of DH and support dermatologists in their diagnostic and therapeutic decisions.

Treatment of granuloma annulare and related granulomatous diseases with sulphasalazine: a series of 16 cases

BACKGROUND

Granuloma annulare (GA) and the related annular elastolytic giant cell granuloma (AEGCG) and interstitial granulomatous dermatitis (IGD) are idiopathic histiocytic inflammatory disorders, which are frequently recalcitrant to treatment.

OBJECTIVES

Evaluate the efficacy of sulphasalazine in treating GA, AEGCG and IGD.

METHODS

Sixteen patients were identified with granulomatous disease who were treated with sulphasalazine between September 2015 and September 2019. Outcomes were based on patients' and providers' subjective evaluations.

RESULTS

Sixteen patients were included in the study (ages 56-89, four male and twelve female). Previous treatments were attempted in fifteen patients. Clinical improvement was seen in fourteen patients (87.5%). Initial improvement was noted within a mean (SD) of 66.4 (35.1) days after starting therapy, with increasing benefits over time. Ten patients (62.5%) reported complete or near-complete clearance, three patients (18.8%) reported significant improvement, and one (6.3%) reported partial improvement. Twelve patients elected to stop or reduce therapy, resulting in relapse or worsening in five patients.

CONCLUSIONS

Sulphasalazine may be considered as treatment for GA and GA-related conditions.

The gut microbiome: an orchestrator of xenobiotic metabolism

Microbes inhabiting the intestinal tract of humans represent a site for xenobiotic metabolism. The gut microbiome, the collection of microorganisms in the gastrointestinal tract, can alter the metabolic outcome of pharmaceuticals, environmental toxicants, and heavy metals, thereby changing their pharmacokinetics. Direct chemical modification of xenobiotics by the gut microbiome, either through the intestinal tract or re-entering the gut via enterohepatic circulation, can lead to increased metabolism or bioactivation, depending on the enzymatic activity within the microbial niche. Unique enzymes encoded within the microbiome include those that reverse the modifications imparted by host detoxification pathways. Additionally, the microbiome can limit xenobiotic absorption in the small intestine by increasing the expression of cell-cell adhesion proteins, supporting the protective mucosal layer, and/or directly sequestering chemicals. Lastly, host gene expression is regulated by the microbiome, including CYP450s, multi-drug resistance proteins, and the transcription factors that regulate them. While the microbiome affects the host and pharmacokinetics of the xenobiotic, xenobiotics can also influence the viability and metabolism of the microbiome. Our understanding of the complex interconnectedness between host, microbiome, and metabolism will advance with new modeling systems, technology development and refinement, and mechanistic studies focused on the contribution of human and microbial metabolism.

Dapsone-induced hepatic complications: it's time to think beyond methemoglobinemia

Drug-induced liver injury is an important cause of hepatotoxicity and poses a challenging clinical problem with respect to both diagnosis and management. Patients susceptible to hepatotoxicity on exposure to dapsone is constantly on the rise. Dapsone (4,4'-diaminodiphenylsulfone) is clinically used alone or in combination with rifampicin for the treatment of a variety of dermatological disorders such as acne, dermatitis herpetiformis, psoriasis, Toxoplasma gondii infections, leprosy and pneumocystis carinii pneumonia in AIDS patients. However, the clinical use of dapsone is limited because of dose-dependent adverse hematological reactions. The cholestatic injury caused by dapsone and its N- hydroxylated metabolites hinders bile flow and causes oxidative stress and hepatic necrosis, further, leading to hemolysis responsible for hepatitis due to iron overload in the liver. Hence, clinicians' awareness of the hepatotoxic potential of dapsone is highly warranted.

The strange connection between epidermal growth factor receptor tyrosine kinase inhibitors and dapsone: from rash mitigation to the increase in anti-tumor activity

The presence of an aberrantly activated epidermal growth factor receptor (EGFR) in many epithelial tumors, due to its overexpression, activating mutations, gene amplification and/or overexpression of receptor ligands, represent the fundamental basis underlying the use of EGFR tyrosine kinase inhibitors (EGFR-TKIs). Drugs inhibiting the EGFR have different mechanisms of action; while erlotinib and gefitinib inhibit the intracellular tyrosine kinase, monoclonal antibodies like cetuximab and panitumumab bind the extracellular domain of the EGFR both activating immunomediated anti-cancer effect and inhibiting receptor function. On the other hand, interleukin-8 has tumor promoting as well as neo-angiogenesis enhancing effects and several attempts have been made to inhibit its activity. One of these is based on the use of the old sulfone antibiotic dapsone that has demonstrated several interleukin-8 system inhibiting actions. Erlotinib typically gives a rash that has recently been proven to come out via up-regulated keratinocyte interleukin-8 synthesis with histological features reminiscent of typical neutrophilic dermatoses. In this review, we report experimental evidence that shows the use of dapsone to improve quality of life in erlotinib-treated patients by ameliorating rash as well as short-circuiting a growth-enhancing aspect of erlotinib based on increased interleukin-8 secretion.

Erlotinib augmentation with dapsone for rash mitigation and increased anti-cancer effectiveness

BACKGROUND

The epidermal growth factor receptor tyrosine kinase inhibitor erlotinib has failed in many ways to be as potent in the anti-cancer role as pre-clinical studies would have suggested. This paper traces some aspects of this failure to a compensatory erlotinib-mediated increase in interleukin-8. Many other-but not all- cancer chemotherapeutic cytotoxic drugs also provoke a compensatory increase in a malignant clone's interleukin-8 synthesis. Untreated glioblastoma and other cancer cells themselves natively synthesize interleukin-8. Interleukin-8 has tumor growth promoting, mobility and metastasis formation enhancing, effects as well as pro-angiogenesis effects.

FINDINGS

The old sulfone antibiotic dapsone- one of the very first antibiotics in clinical use- has demonstrated several interleukin-8 system inhibiting actions. Review of these indicates dapsone has potential to augment erlotinib effectiveness. Erlotinib typically gives a rash that has recently been proven to come about via an erlotinib triggered up-regulated keratinocyte interleukin-8 synthesis. The erlotinib rash shares histological features reminiscent of typical neutrophilic dermatoses. Dapsone has an established therapeutic role in current treatment of other neutrophilic dermatoses.

CONCLUSION

Thus, dapsone has potential to both improve the quality of life in erlotinib treated patients by amelioration of rash as well as to short-circuit a growth-enhancing aspect of erlotinib when used in the anti-cancer role.

The efficacy of 5% dapsone gel plus oral isotretinoin versus oral isotretinoin alone in acne vulgaris: A randomized double-blind study

Background:

Acne vulgaris, a common human skin condition, is an inflammatory disease characterized by comedones, papules, nodules and possibly scarring.

This study aimed to evaluate the efficacy of a combination of 5% dapsone gel plus oral isotretinoin in the treatment of acne vulgaris.

Materials and Methods:

A randomized, placebo-controlled, study was carried out on patients with moderate to severe acne. The patients were randomly divided in two groups: (dapsone gel and vehicle gel). All Patients were administered oral isotretinoin 20 mg daily and topical gel twice a day for 8 weeks. The Global Acne Assessment Score (GAAS), the number lesions and side-effects were documented at base line and weeks 4, 8 and 12.

Results:

A total of 58 patients (age range: 18-25 years) were included in our study. The number of lesions was significantly lower in the dapsone-treated group at all follow-up visits (P < 0.001). The mean GAAS score in the dapsone-treated group and in the Placebo-treated group decreased, but there was no statistical difference in two groups (P < 0.001). The side-effects on the dapsone-treated group were a mild burning sensation in 7 patients (24.13%), mild erythema of the skin and mild dryness in 4 (13.79%) and 3 (10.34%) cases respectively (P < 0.001). In our study, adverse effects were common but they were minor and tolerable. No clinically significant changes in laboratory parameters were observed (P < 0.001).

Conclusions:

Dapsone gel was an effective medication for patients who received isotretinoin for acne vulgaris treatment resulting in a significant reduction of the number of lesions.

Nanoemulsion containing dapsone for topical administration: a study of in vitro release and epidermal permeation

BACKGROUND

Topical administration of dapsone can be an alternative route for treatment of leprosy and can also provide new therapeutic applications for an established drug. However, the physicochemical properties of dapsone make it difficult to incorporate into conventional formulations. The current study was directed toward developing a stable nanoemulsion that contains dapsone which can be adapted for topical use.

METHODS

Nanoemulsions were prepared using isopropyl myristate or n-methyl-pyrrolidone as the oil phase, and characterized according to their mean droplet size, conductivity, refractive index, pH, drug content, and stability. The in vitro release of dapsone and its ability to permeate the epidermis were also evaluated.

RESULTS

Physicochemical characterization demonstrated that nanosystems were formed, which had a uniform droplet distribution and a pH compatible with the skin surface. Use of n-methyl-pyrrolidone provided a greater nanoemulsion region and higher solubilization of dapsone, and increased the in vitro release rate when compared with a nanoemulsion prepared using isopropyl myristate. However, use of isopropyl myristate promoted an increase in in vitro epidermal permeation that followed the Higuchi model. This demonstrates the ability of a nanosystem to influence permeation of dapsone through the skin barrier. Furthermore, the nanoemulsions developed and evaluated here had ideal physicochemical stability over a 3-month period.

CONCLUSION

Incorporation of dapsone into a nanoemulsion may be a promising system for enabling topical delivery of dapsone, while minimizing skin permeation, for the treatment of acne. The method developed here used isopropyl myristate as the oil phase, and promoted permeation of dapsone through the skin barrier for the treatment of leprosy upon use of n-methyl-pyrrolidone as the oil phase.

Lúpus eritematoso sistêmico bolhoso: diagnóstico diferencial com dermatite herpetiforme

O lúpus eritematoso sistêmico bolhoso é um subtipo raro do lúpus eritematoso sistêmico, que ocorre ainda de forma mais incomum nos pacientes pediátricos. Relatamos o caso de uma adolescente de 12 anos, apresentando lesões vésico-bolhosas em face, pescoço, tronco, mucosas oral e genital, anemia, leucocitúria estéril, FAN: 1/1280 padrão nuclear pontilhado grosso, Anti-Sm e Anti-RNP positivos. O estudo anatomopatológico sugere dermatite herpetiforme e a imunofluorescência direta revela IgG, IgA e fibrina ao longo da zona de membrana basal. Apresentamos um caso típico de lúpus eritematoso sistêmico bolhoso e enfatizamos a importância do diagnóstico diferencial com a dermatite herpetiforme

Approach to the patient with autoimmune mucocutaneous blistering diseases

Autoimmune mucocutaneous blistering diseases (AMBD) are a rare group of dermatoses that can be potentially fatal. There are many subtypes and their clinical presentation can vary from being localized to general involvement. It is crucial that a diagnosis be made as early as possible and appropriate treatments are implemented. This article will discuss the diagnosis and available treatments of the major AMBDs. There are very few case-controlled studies regarding the treatments of these diseases. Most of the treatments used for these diseases are based on anecdotal reports. Hence, a synopsis of the conventional treatments and some brief recommendations will also be discussed. A brief discussion regarding "rescue" therapies that have been used for those patients with more recalcitrant cases of AMBD will also be presented.

Celiac sprue: a unique autoimmune disorder

Celiac sprue (CS) is a gluten-sensitive enteropathy with many autoimmune features. CS involves multiple organs through immune and nonimmune processes, and is frequently associated with other autoimmune disorders. This article reviews the co-occurrence of CS with autoimmune disorders of the cutaneous, nervous, endocrine, musculoskeletal, gastrointestinal and cardiovascular systems. The types of autoimmune disorders associated with CS and the prevalence of CS in other autoimmune disorders are also discussed. A brief review of the literature on the potential mechanisms behind these associations and the therapeutic effects of a gluten-free diet for autoimmune comorbidities in CS is also provided.

A long‐term gluten‐free diet as an alternative treatment in severe forms of dermatitis herpetiformis

BACKGROUND

A long-term gluten-free diet (GFD) as a first-choice treatment for dermatitis herpetiformis (DH) has been used successfully. The aim of the present study is to evaluate the possibility of treating all severe skin manifestations of DH by a GFD only.

METHODS

Seventy-two patients with DH were subdivided in two groups: group A (18 patients) underwent a GFD and received dapsone; group B (54 patients) underwent a GFD. Patients were subdivided into slight, moderate and severe forms.

RESULTS

A total of 88.9% of patients treated with dapsone and a GFD (group A) had remission of skin manifestations and the remaining 11.1% were improved. In group B, 87% of patients showed complete remission of skin manifestations after 18 months of a GFD; 13% showed improvement. With regard to severe forms, after an 18-month treatment, 70.4% of patients in group B; 66.6% in group A.

CONCLUSION

Our study shows that a GFD, if administered steadily and for a long period, can be a valid treatment for severe forms of DH. Dapsone can be useful to control the inflammatory phase of the disease.

Pharmacokinetics of Dapsone Gel, 5% for the Treatment of Acne Vulgaris

BACKGROUND

Oral dapsone has been available for over 60 years and has been used to treat severe acne vulgaris; however, the oral formulation is known to cause dose-dependent haematological reactions and is currently indicated only for diseases such as dermatitis herpetiformis and Hansen's disease. A gel formulation of dapsone was recently developed to treat acne vulgaris. As dapsone is administered topically, it was expected that systemic absorption would be considerably lower than that observed with oral dapsone therapy, thereby avoiding any adverse haematological effects.

OBJECTIVE

To report the pharmacokinetic profile of topically applied dapsone gel, 5% in the treatment of acne vulgaris.

STUDY PARTICIPANTS AND METHODS

Three prospective, open-label studies enrolled a total of 548 subjects with acne vulgaris: two phase I pharmacokinetic studies (crossover and drug interaction) and one phase III long-term safety study. In the crossover study (n = 18), topical dapsone gel applied twice daily for a total of 14 days to 22.5% of the body surface area was compared with a single dose of oral dapsone 100mg (the typical clinical dose). In the drug-interaction study (n = 24), oral trimethoprim/sulfamethoxazole monotherapy, topical dapsone gel monotherapy and the two in combination were used twice daily for 7, 21 and 7 days, respectively. In the long-term safety study (n = 506), topical dapsone gel was applied twice daily to acne-affected areas for up to 12 months. Blood samples were drawn at various timepoints in each study to assess drug and metabolite concentrations. Systemic concentrations of dapsone, N-acetyl dapsone, dapsone hydroxylamine, trimethoprim and sulfamethoxazole were determined, according to the study design.

RESULTS

In the crossover study, the mean area under the plasma concentration-time curve (AUC) from 0 to 24 hours for dapsone was 417.5 ng x h/mL after 2 weeks of dapsone gel therapy (n = 10), compared with an AUC from time zero to infinity of 52,641 ng x h/mL after a single dose of oral dapsone; this represents a 126-fold lower systemic exposure for dapsone gel at typical therapeutic doses. In the drug-interaction study, the AUC from 0 to 12 hours for dapsone was 221.52 ng x h/mL after 3 weeks of dapsone gel monotherapy compared with 320.3 ng x h/mL after 1 week of coadministration with trimethoprim/sulfamethoxazole. In the long-term safety study, the mean plasma dapsone concentrations ranged from 7.5 to 11 ng/mL over 12 months. Overall, total systemic exposures to dapsone and its metabolites were approximately 100-fold less for dapsone gel than for oral dapsone, even in the presence of trimethoprim/sulfamethoxazole. There were no reports of any haematological adverse events.

CONCLUSIONS

Topical application of dapsone gel in various settings ranging from 2 weeks to 12 months resulted in systemic exposures to dapsone and its metabolites that were approximately 100-fold less than those after oral dapsone at a therapeutic dose level. The concentrations of dapsone and its metabolites reached steady state and did not increase during prolonged treatment.

Loxoscelism

Loxoscelism (bites by spiders of the genus Loxosceles) is the only proven arachnological cause of dermonecrosis. Although Loxosceles spiders can be found worldwide, their distribution is heavily concentrated in the Western Hemisphere, particularly the tropical urban regions of South America. Although Loxosceles bites are usually mild, they may ulcerate or cause more severe, systemic reactions. These injuries mostly are due to sphingomyelinase D in the spider venom. There is no proven effective therapy for Loxosceles bites, although many therapies are reported in the literature.

Evaluation of the clinical, immunologic, and biochemical effects of nitroso sulfamethoxazole administration to dogs: a pilot study

Sulfonamide antimicrobials such as sulfamethoxazole (SMX) have been associated in humans with hypersensitivity reactions, to include fever, skin eruptions, hepatotoxicity, and blood dyscrasias. These reactions also occur in dogs, the only non-human species known to develop a similar spectrum of sulfonamide hypersensitivity. Sulfonamide hypersensitivity is not well understood, but has been hypothesized to be due to the generation of the reactive oxidative metabolite, nitroso sulfamethoxazole (SMX-NO). SMX-NO, unlike the parent sulfonamide, is cytotoxic in vitro, haptenizes tissue proteins, and is immunogenic in rodents. The purpose of this pilot study was to determine whether SMX-NO, when administered to dogs, would lead to drug-tissue adducts, anti-drug antibodies, antioxidant depletion, or clinical evidence of drug hypersensitivity. Four dogs were randomized to one of four treatments: SMX-NO 1 mg/kg; SMX-NO 3 mg/kg; SMX-NO 10 mg/kg; or vehicle control. Dosing was by the intraperitoneal route, once daily for four consecutive days per week, for 2 weeks total, followed by a third week of observation. Following this, all dogs were challenged with trimethoprim-sulfamethoxazole, 25 mg/kg for 12 h for 2 weeks. No dog developed clinical or biochemical evidence of drug hypersensitivity. Plasma cysteine and leukocyte reduced glutathione were not depleted during dosing; however, ascorbate was significantly depleted by week 2 following SMX-NO at 10 mg/kg. Anti-SMX antibodies (IgG or IgM by ELISA) were not detected in any dogs at any time points. SMX-hemoglobin adducts were detected in the spleen in SMX-NO dosed dogs; however, these adducts were not accompanied by an immunologic or systemic response. The results of this pilot study indicate that SMX-NO dosing in dogs, using a dosing protocol shown to be immunogenic in other species, produces modest ascorbate depletion and hemoglobin adduct formation, but is insufficient to produce an immunologic response or a clinical syndrome of sulfonamide hypersensitivity in this susceptible species.

Optimal treatment of pyoderma gangrenosum

The optimal treatment of pyoderma gangrenosum includes a combination of local wound care and systemic medications. Oral and pulse intravenous corticosteroids have traditionally been the most commonly recommended first-line systemic therapies. Cyclosporine, with or without corticosteroids, has more recently emerged as a first-line systemic treatment. A multitude of immunosuppressive and immune-modulating medications, as well as antimicrobial agents with anti-inflammatory properties have also been widely prescribed. Often, it is difficult to achieve control of aggressive cases of pyoderma gangrenosum, necessitating administration of a combination of systemic therapies. Furthermore, patients recalcitrant to one or many medications are frequently reported. Concomitant disease, intolerance to a class of medications, and the patient's response to prior therapies can help guide a practitioner in choosing the optimal treatment of pyoderma gangrenosum.

Inaccurate glycosylated hemoglobin A1C measurements in human immunodeficiency virus-positive patients with diabetes mellitus

Persistent differences in blood glucose and serum glycosylated hemoglobin (HbA1C) measurements were observed in 4 human immunodeficiency virus-positive patients with diabetes mellitus, all of whom were taking drugs associated with hemolysis, which interferes with the reliability of HbA1C levels. Determination of fructosamine levels was a more accurate alternative for measuring average glycemic control in these patients.

Sweet's syndrome: a review of current treatment options

Sweet's syndrome was originally described in 1964 by Dr Robert Douglas Sweet as an 'acute febrile neutrophilic dermatosis'. The syndrome is characterized by pyrexia, elevated neutrophil count, painful red papules, nodules, plaques (which may be recurrent) and an infiltrate consisting predominantly of mature neutrophils that are diffusely distributed in the upper dermis. In addition to skin and mucosal lesions, Sweet's syndrome can also present with extra-cutaneous manifestations. Sweet's syndrome can be classified based upon the clinical setting in which it occurs: classical or idiopathic Sweet's syndrome, malignancy-associated Sweet's syndrome and drug-induced Sweet's syndrome. Systemic corticosteroids have been considered the 'gold standard' for the treatment of patients with Sweet's syndrome; in addition, treatment with topical and/or intralesional corticosteroids may be effective as either monotherapy or adjuvant therapy. However, spontaneous resolution of the symptoms and lesions has occurred in several patients with Sweet's syndrome for whom disease-specific therapeutic intervention was not initiated and in some of the patients with drug-induced Sweet's syndrome after withdrawal of the dermatosis-causing medication. Oral therapy with either potassium iodide or colchicine typically results in rapid resolution of Sweet's syndrome symptoms and lesions; therefore, in patients with Sweet's syndrome who have a potential systemic infection or in whom corticosteroids are contraindicated, it is reasonable to initiate treatment with these agents as a first-line therapy. Indomethacin, clofazimine, dapsone, and cyclosporine have also been effective therapeutic agents for managing Sweet's syndrome. However, indomethacin and clofazimine appear less effective than corticosteroids, potassium iodide, and colchicine. Appropriate initial and follow-up laboratory monitoring is necessary when treating with either dapsone or cyclosporine because of the potential for severe adverse drug-associated effects. Systemic antibacterials with activity against Staphylococcus aureus frequently result in partial improvement of Sweet's syndrome lesions when they are impetiginized or secondarily infected. In some patients with dermatosis-associated bacterial infections, organism-sensitive specific systemic antibacterials have been helpful in the management of their Sweet's syndrome. Although patients with hematologic malignancy-associated Sweet's syndrome often receive cytotoxic chemotherapy agents and antimetabolic drugs for the treatment of their underlying disorder, these agents are seldom used solely for the management of the symptoms and lesions of Sweet's syndrome. The treatment of patients with Sweet's syndrome with either etretinate or interferon-alpha have been reported as single case reports; both patients had improvement of not only their Sweet's syndrome lesions, but also their associated hematologic disorder.