Minocycline hydrochloride hyperpigmentation complicating treatment of pyoderma gangrenosum

The Pathophysiology and Treatment of Pyoderma Gangrenosum-Current Options and New Perspectives

Pyoderma gangrenosum (PG) is an uncommon inflammatory dermatological disorder characterized by painful ulcers that quickly spread peripherally. The pathophysiology of PG is not fully understood; however, it is most commonly considered a disease in the spectrum of neutrophilic dermatoses. The treatment of PG remains challenging due to the lack of generally accepted therapeutic guidelines. Existing therapeutic methods focus on limiting inflammation through the use of immunosuppressive and immunomodulatory therapies. Recently, several reports have indicated the successful use of biologic drugs and small molecules administered for coexisting diseases, resulting in ulcer healing. In this review, we summarize the discoveries regarding the pathophysiology of PG and present treatment options to raise awareness and improve the management of this rare entity.

Management of neutrophilic dermatoses

Neutrophilic dermatoses, including Sweet's syndrome, pyoderma gangrenosum, and rheumatoid neutrophilic dermatitis, are inflammatory conditions of the skin often associated with underlying systemic disease. These are characterized by the accumulation of neutrophils in the skin. The associated conditions, potential for systemic neutrophilic infiltration, and therapeutic management of these disorders can be similar. Sweet's syndrome can often be effectively treated with a brief course of systemic corticosteroids. Pyoderma gangrenosum, however, can be recurrent, and early initiation of a steroid-sparing agent is prudent. Second-line treatment for both of these conditions includes medications affecting neutrophil function, in addition to immunosuppressant medications.

Safety of doxycycline and minocycline: a systematic review

OBJECTIVE

The goal of this review was to summarize the available literature covering the safety profiles of oral doxycycline and minocycline.

METHODS

Scientific literature published between 1966 and August 2003 was searched using the MEDLINE, EMBASE, and Biosis databases (search terms: minocycline or doxycycline, each paired with adverse reaction, adverse event, and side effect, and doxycycline or minocycline with the limits English language, human, and clinical trials). Safety information was collected from case reports and clinical trials. Adverse event (AE) rates in the United States were calculated by comparing data from the MedWatch AE reporting program used by the US Food and Drug Administration (FDA) with the number of new prescriptions dispensed for each drug from January 1998 to August 2003.

RESULTS

Between 1966 and 2003, a total of 130 and 333 AEs were published in case reports of doxycycline and minocycline, respectively. In 24 doxycycline clinical trials (n = 3833) and 11 minocycline trials (n = 788), the ranges in incidence of AEs were 0% to 61% and 11.7% to 83.3%, respectively. Gastrointestinal AEs were most common with doxycycline; central nervous system and gastrointestinal AEs were most common with minocycline. From January 1998 to August 2003, the FDA MedWatch data contained 628 events for doxycycline and 1099 events for minocycline reported in the United States. Approximately 47,630,000 doxycycline and 15,234,000 minocycline new prescriptions were dispensed in the United States during that period, yielding event rates of 13 per million for doxycycline and 72 per million for minocycline, based on FDA data.

CONCLUSIONS

Between 1998 and 2003, doxycycline was prescribed 3 times as often as minocycline. The incidence of AEs with either drug is very low, but doxycycline had fewer reported AEs. Although more head-to-head clinical trials are needed for a direct comparison of AE frequency, these preliminary data from separate reports suggest the possibility that AEs may be less likely with doxycycline than minocycline.

Therapy Insight: pyoderma gangrenosum—old disease, new management

Well-designed studies that help guide physicians to apply the optimal therapeutic strategy for the management of pyoderma gangrenosum are lacking in the literature. A multidisciplinary approach is paramount for the effective management of this condition, with close involvement of a wound-care specialist and a microbiologist. Treatment should be stepwise in nature. Local wound care, avoidance of trauma and the application of local steroid or tacrolimus ointment are the first-line treatments. Steroid therapy is the most widely published effective therapy for achieving resolution of pyoderma gangrenosum, although there is growing evidence for the efficacy of infliximab in refractory cases. Other therapies such as dapsone and clofazamine should be left as third-line agents for refractory pyoderma gangrenosum, while novel treatments such as granulocyte apheresis should only be used under trial conditions, to gain an objective evaluation of their efficacy. This article reviews the published treatment strategies in current use, and aims to guide the effective management of pyoderma gangrenosum.

Pyoderma gangrenosum: an inflammatory ulcer

A review of this condition is presented and a case report of a patient who developed pyoderma gangrenosum in association with myelodysplastic syndrome is described