Images in clinical medicine. Gouty tophi

Metabolic characteristics and renal dysfunction in 65 patients with tophi prior to gout

Tophi typically occur many years after uncontrolled gout. Therefore, their development before gout remains unusual. Such patients might exhibit some characteristic differences compared with typical tophaceous gout patients. In this study, 65 tophaceous gout patients with tophi as the first sign of gout (tophi-first group) were enrolled. Their clinical characteristics were compared with those of 1421 patients whose tophi occurred after gout (tophi-after group). Compared with the tophi-after group, the tophi-first group had a significantly higher percentage of female patients and patients with elderly onset of disease and a lower percentage of patients with a positive family history; these patients had lower body mass indices, serum urate levels, and estimated glomerular filtration rates (eGFRs). Female sex and negative family history were identified as the principal determinants of tophi development before gout. The decreasing eGFR among the tophi-first group was not due to the group per se but was a result of older age, longer tophi duration, and hyperuricemia. The most common site of initial tophi occurrence in both groups was the toe. In the tophi-first group, the occurrence rates for initial tophi sites were significantly higher at the finger but were lower at the ankle. The tophi-first group exhibited distinct characteristics of age, gender, family history, BMI, serum urate levels, and initial tophi site. This group had fewer comorbidities but similar renal dysfunction compared with the tophi-after group. Thus, patients presenting with tophi should be treated promptly, even if they have no history of gout symptoms.

Granulomatous disorders

Almost all granulomatous skin disorders can cause red lesions on the face. Such disorders may include many bacterial, fungal, or parasitic infections, noninfectious inflammatory disorders, foreign body reactions, and even neoplasms. Clinically, they usually present with papules, plaques, nodules, and/or abscesses, which may ulcerate. It may be helpful in their differential diagnosis to define certain clinical patterns, such as multiple and discrete papules, necrotic or umbilicated papules or nodules, annular plaques, vegetative plaques or tumors, verrucous plaques or tumors, abscesses and/or sinuses, and lymphocutaneous pattern. Some disorders, such as sarcoidosis, can cause a wide variety of lesions. We accept that cutaneous leishmaniasis is also among such great imitators.