Trichoepithelioma: A Comprehensive Review.

Trichoepithelioma is an uncommon benign adnexal neoplasm. It can present as a solitary non-familial or multiple familial form. Trichoepithelioma usually develops in early childhood or puberty. Females are more affected. It is attributed to two genetic mutations on chromosomes 9p21 and 16q12-q13. Multiple familial trichoepithelioma is an autosomal-dominant disorder, characterized by numerous nodules and papules, predominantly on the face and occasionally on the scalp, neck, or upper trunk, positive family history, and histopathological findings. The lesions gradually increase in both size and number over time; however, they remain mostly asymptomatic. Although it is rare, trichoepithelioma lesions can undergo malignant transformation to trichoblastic carcinoma or basal cell carcinoma. Patients mainly seek treatment because the lesions are usually disfiguring and can lead to psycho-social issues. Non-pharmacologic approaches (e.g., excisional surgery, laser resurfacing), as the current mainstay of management, suffer from several drawbacks. New treatment techniques such as pharmacotherapy with potentially effective agents deserve more attention and investigation.

Serum cystatin C as a marker of renal function in critically ill patients with normal serum creatinine.

BACKGROUND: Serum creatinine as a classic marker of renal function has several limitations in the detection of renal dysfunction. OBJECTIVES: This study assessed the validity of serum cystatin C as a marker of renal function in critically ill patients with normal serum creatinine. PATIENTS AND METHODS: Eighty adult patients referred to intensive care units with serum creatinine levels < 1.5 mg/dL and without hemodynamic instability were chosen and their serum creatinine and cystatin C levels were measured. A 24-hour urine sample was collected to calculate creatinine clearance (Ccr). Renal dysfunction was defined as Ccr < 80 mL/min/1.73 m(2). RESULTS: There were significant correlations between measured Ccr and 1/serum creatinine (R = 0.51, P < 0.001) and 1/serum cystatin C (R = 0.25, P = 0.028). The difference between false negative rates of serum creatinine (93.33%) and cystatin C (80%) in the detection of renal dysfunction was significant (P = 0.032). Receiver operating characteristic curve analysis illustrated that area under the curve of serum creatinine and cystatin C for detecting renal dysfunction were 0.711 and 0.607, respectively; however, this difference was not significant (P = 0.222). CONCLUSIONS: Our data demonstrated that serum cystatin C is not superior to serum creatinine in the early detection of renal dysfunction in critically ill patients.