Lott JP, Girardi M. Practice Gaps —The Hard Task of Measuring Cutaneous Fibrosis. Arch Dermatol. 2011;147(9):1115-1116. doi:10.1001/archdermatol.2011.244
Author Affiliations: Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut.
Cutaneous fibrosing disorders (CFDs) —including scleroderma, chronic graft-vs-host disease, and nephrogenic systemic fibrosis —are devastating skin diseases, variably involving subcutaneous tissues and internal organs and potentially resulting in debilitating morbidity and substantial mortality. Provision of effective interventions for management of cutaneous complications of CFDs, including progressive skin induration, joint restriction, cutaneous dysesthesias, and recalcitrant pruritus, remains challenging. Fortunately, several pharmacologic agents in development purportedly inhibit the underlying cytokine cascades that lead to abnormal collagen production, and others may potentially even permit the reversal of established fibrosis.
Evaluating the response of patients with CFD to these novel therapies will require accurate and reproducible assessment of skin disease activity and damage —measures that, to date, are largely lacking. However, the dermatologic community has developed reliable clinical instruments for quantifying skin disease activity in several other chronic skin conditions, notably the Psoriasis Area and Severity Index (PASI) for psoriasis and the Severity Weighted Assessment Tool (SWAT) for mycosis fungoides. Moreover, use of full-body digital imaging and analysis to identify and precisely quantify areas of involved skin has continued to improve the accuracy of these tools.
Unfortunately, such instruments have proven difficult to export to the realm of CFD, which may harbor dermal, subcutaneous, and fascial involvement that is often not easily appreciated by visual inspection and palpation alone.1 Various technologies have been developed to address these challenges, including durometers for measuring skin hardness and/or tautness, cutometers for quantifying skin elasticity, and ultrasonographic devices for assessing local dermal and subcuta-neous blood flow, as outlined by Nezafati et al, but each requires multiple, time-consuming measurements that are subject to significant interuser and intrauser variability as well as within-patient sampling error. Thermographic global heat mapping partially overcomes these problems through simultaneous assessment of large areas of skin, but it too is also prone to error.
Clearly, an unmet need for patients with CFD are new devices and accompanying strategies for efficient and objective assessment of skin fibrosis. Ideally, measurement of disease activity and therapeutic response in patients with CFD would combine (1) automated full-body scanning, (2) global superficial cutaneous assessments (eg, epidermal integrity, barrier function), and (3) global evaluation of the dermis and subcutis (eg, elasticity, induration, blood flow) —yielding data to develop and improve scoring metrics to guide ongoing patient care. Recent experimental techniques such as scanning laser vibrometry and surface wave analysis2 are probable steps in the right direction and may yield benefit if incorporated into new multimodal assessment paradigms.
At present, dermatologists should strive to augment their clinical assessment of CFD activity (including, for example, estimates of joint-mobility, range-of-motion, and quality-of-life surveys) with 1 or more of the existing technologies to monitor their patients' disease activity. The resulting gestalt will, for now, have to suffice.
Correspondence: Dr Girardi, Department of Dermatology, Yale University School of Medicine, 333 Cedar St, New Haven, CT 06520 (firstname.lastname@example.org).
Financial Disclosure: None reported.