Teledermatology. Current status and future directions.

Teledermatology is becoming an increasingly common means of delivering dermatologic healthcare worldwide and will almost certainly play a greater role in the future. The type of technology used distinguishes the 2 modes of teledermatology consultation. The store and forward technique uses still digital images generated by a digital camera. Consultations of this type are considered asynchronous since the images are obtained, sent, and reviewed at different times. In contrast, real-time interactive consultations are synchronous. Patients and clinicians interact in real-time through an audio-video communication link. Each modality has its advantages and disadvantages, and studies appear in the literature that assess both technologies. Although diagnostic reliability (precision) assessments for teledermatology are subject to limitations, existing information indicates that both store and forward and real-time interactive technology result in reliable diagnostic outcomes when compared with clinic-based evaluations. Less information regarding diagnostic accuracy is available; however, one evaluation that used store and forward technology found comparable diagnostic accuracy between teledermatology consultations and clinic-based examinations. Currently, little information is available regarding cost effectiveness and patient outcomes. Existing evidence, while inconclusive, suggests that teledermatology may be more costly than traditional clinic-based care, especially when using real-time interactive technology. Teledermatology has been shown to have utility as a triage mechanism for determining the urgency or need for a clinic-based consultation. Overall, patients appear to accept teledermatology and are satisfied with it as a means of obtaining healthcare. Clinicians have also generally reported positive experiences with teledermatology. Future studies that focus on cost effectiveness, patient outcomes, and patient and clinician satisfaction will help further define the potential of teledermatology as a means of dermatologic healthcare delivery.

Reliability and accuracy of dermatologists' clinic-based and digital image consultations.

BACKGROUND: Telemedicine technology holds great promise for dermatologic health care delivery. However, the clinical outcomes of digital image consultations (teledermatology) must be compared with traditional clinic-based consultations. OBJECTIVE: Our purpose was to assess and compare the reliability and accuracy of dermatologists' diagnoses and management recommendations for clinic-based and digital image consultations. METHODS: One hundred sixty-eight lesions found among 129 patients were independently examined by 2 clinic-based dermatologists and 3 different digital image dermatologist consultants. The reliability and accuracy of the examiners' diagnoses and the reliability of their management recommendations were compared. RESULTS: Proportion agreement among clinic-based examiners for their single most likely diagnosis was 0. 54 (95% confidence interval [CI], 0.46-0.61) and was 0.92 (95% CI, 0. 88-0.96) when ratings included differential diagnoses. Digital image consultants provided diagnoses that were comparably reliable to the clinic-based examiners. Agreement on management recommendations was variable. Digital image and clinic-based consultants displayed similar diagnostic accuracy. CONCLUSION: Digital image consultations result in reliable and accurate diagnostic outcomes when compared with traditional clinic-based consultations.

A pilot trial of digital imaging in skin cancer.

We have used inexpensive off-the-shelf equipment for store-and-forward teledermatology and compared the precision and accuracy of digital image consultations with conventional, clinic-based consultations. Thirteen lesions were studied on 12 patients referred to a dermatology clinic for a suspected skin cancer. Patients were examined by two dermatologists. Subsequently, digital images were examined by two different dermatologists. There was almost complete agreement, both among and between the clinical and digital examiners, on different diagnosis and biopsy recommendations. Agreement on the single most likely diagnosis was also good. Digital imaging shows promise in teledermatology.

The rational clinical examination. Does this patient have a mole or a melanoma?

Lifetime risk for malignant melanoma has increased from 1 in 1500 in the United States in 1930 to 1 in 75 projected for the year 2000. Because the tumor's thickness at excision is the primary prognostic determinant, early detection through the history and physical examination can play an important role in the patient's clinical course. Two checklists have been developed as diagnostic aids, the ABCD (A indicates asymmetry; B, border irregularity; C, irregular color; and D, diameter >6 mm) and the revised 7-point checklists. These checklists should be interpreted with some discretion, but 2 studies have found the sensitivity for the ABCD checklist to be 92% (95% confidence interval [CI], 82%-96%) and 100% (95% CI, 54%-100%); 1 study found the specificity to be 98% (95% CI, 95%-99%). The revised 7-point checklist has been reported to have a sensitivity of 79% (95% CI, 70%-85%) to 100% (95% CI, 94%-100%) and specificity of 30% (95% CI, 21%-39%) to 37% (95% CI, 28%-46%). Physicians' global assessments for detecting the presence or absence of melanoma are estimated to have a specificity of 96% to 99%, while sensitivity ranges widely from 50% to 97%. Nondermatologists' examinations appear to be less sensitive than examinations performed by dermatologists.

Primary care clinicians' performance for detecting actinic keratoses and skin cancer.

BACKGROUND: If skin cancer screening is to become widely adopted, its effectiveness depends on the ability of primary care clinicians to detect cutaneous malignancies. OBJECTIVE: To assess primary care clinicians' proficiency for detecting skin cancers and actinic keratoses in a clinic population. METHODS: A convenience sample of 190 white male patients aged 40 years or older presenting to a university-affiliated Veterans Affairs general internal medicine or dermatology clinic were included in the study. Each patient was independently examined by a primary care clinician and a dermatologist to measure interobserver agreement. We compared the ability of primary care clinicians to diagnose actinic keratoses and skin cancers using dermatologists' examinations as a pragmatic reference standard. RESULTS: Agreement was moderate as to whether a patient had single actinic keratosis (kappa, 0.36; 95% confidence interval [CI], 0.22-0.50), multiple actinic keratoses (kappa, 0.48; 95% CI, 0.34-0.61), or skin cancer (kappa, 0.48; 95% CI, 0.34-0.62). Agreement decreased when individual lesions were the unit of analysis. When the patient was the unit of analysis, primary care clinicians identified the presence of skin cancer with a sensitivity of 57% (95% CI, 44%-68%), specificity of 88% (95% CI, 81%-93%), positive likelihood ratio of 4.9 (95% CI, 3.0-8.3), and negative likelihood ratio of 0.48 (95% CI, 0.35-0.63). When the lesion was the unit of analysis the sensitivity was 38% (95% CI, 29%-47%), the specificity was 95% (95% CI, 93%-96%), the positive likelihood ratio was 7.1 (95% CI, 4.8-10.3), and the negative likelihood ratio was 0.66 (95% CI, 0.56-0.75). CONCLUSIONS: Examinations performed by primary care clinicians for diagnosing skin cancer lacked sensitivity. Without improved diagnostic skills, primary care clinicians' examinations may be ineffective as a screening test.

The influence of history on interobserver agreement for diagnosing actinic keratoses and malignant skin lesions.

BACKGROUND: Quantifying interobserver diagnostic agreement is necessary to evaluate skin cancer screening programs, but estimates of variability are incomplete. OBJECTIVE: We sought to measure agreement between dermatologists for diagnosing actinic keratoses (AKs) and malignant skin lesions and to determine the way in which blinding examiners to patient history affects agreement. METHODS: We varied the amount of historical information available to examiners in two consecutive patient series (n = 50) presenting to a Veterans Affairs Medical Center dermatology clinic. Two dermatologists examined each patient independently. RESULTS: Assessing historical features increased the kappa statistic for malignancy recognition from -0.04 to 0.76. kappa Statistics for diagnosing single AKs were 0.17 and 0.15, respectively, and 0.62 and 0.55 for multiple AKs. CONCLUSION: Agreement was high for diagnosing malignant skin lesions when history was included in the evaluation. Agreement for multiple AKs was higher than for single AKs, although neither was influenced by inclusion of historical features.

Guillain-Barre syndrome. Another immune-mediated disease with a predilection for young women?

Although the epidemiology of Guillain-Barre syndrome (GBS) has been studied extensively, some important aspects remain unrecognized. In a retrospective study of 92 patients with GBS, we identified an apparent increased frequency in young women, an epidemiological feature shared with other immune-mediated neurological diseases such as myasthenia gravis and multiple sclerosis.