A recent study found that patients with prurigo nodularis had relatively greater abnormalities identified on metabolic, renal, hepatic, hematologic, and endocrine laboratory testing compared to healthy controls.
Prurigo nodularis is a chronic dermatological condition that is associated with different systemic comorbidities. The current medical literature lacks adequate evidence to support laboratory testing in the diagnosis of prurigo nodularis patients.
This cross-sectional study published in JAAD International assessed the severity and frequency of abnormalities in peripheral blood laboratory testing in the diagnostic workup of patients with prurigo nodularis compared to healthy controls.
Study Characteristics
This cross-sectional study included 12,157 prurigo nodularis patients and 12,157 matched controls. The mean age of the study participants was 57.9 ± 16 years. Approximately 59.9% of the study participants were female, and approximately 19.9% of the study cohort were African American.
Routine Laboratory Parameters in Prurigo Nodularis
The measurement of routine laboratory parameters indicated significantly higher abnormal values in prurigo nodularis patients compared to healthy controls. This included an ungraded increase in neutrophils and eosinophils, a grade 2 decrease in hemoglobin levels, and a grade 2 increase in the levels of lymphocytes.
Hepatic Enzyme Markers in Prurigo Nodularis
The liver enzyme markers, bilirubin, and albumin were altered in a greater proportion of patients with prurigo nodularis compared to healthy controls. The prurigo nodularis patients demonstrated grade 2 increases in levels of alanine aminotransferase, grade 2 and grade 3 increases in alkaline phosphatase levels, and grade 3 increases in aspartate aminotransferase. Regarding hepatically produced markers, the prurigo nodularis patients experienced a grade 2 increase in total bilirubin, a grade 3 increase in direct bilirubin, and a grade 2 decrease in albumin.
Endocrine and Renal Laboratory Abnormalities in Prurigo Nodularis
Higher proportions of abnormalities in renal and endocrine laboratory parameters were observed in patients with prurigo nodularis compared to healthy controls. The patients experienced signs reflecting worse renal function, higher levels of blood urea nitrogen, grades 2–4 decreases in the estimated glomerular filtration rate, and increases in all graded levels of serum creatinine.
Endocrine Dysfunction Markers in Prurigo Nodularis Patients
The prurigo nodularis patients demonstrated endocrine dysfunction signs, represented by significantly higher diabetic-level hemoglobin A1c and alterations in the levels of thyroid-stimulating hormone. Compared to the controls, higher proportions of prurigo nodularis patients had an elevated erythrocyte sedimentation rate.
This study supports the potential role of systemic laboratory testing in the diagnosis of prurigo nodularis.
Source:
Cornman, H., Deng, J., Kambala, A., Parthasarathy, V., Reddy, S. V., & Kwatra, S. G. (2023). Clinical utility of peripheral blood laboratory testing in the diagnostic workup of prurigo nodularis patients: a multicenter cohort study. JAAD International. https://doi.org/10.1016/j.jdin.2023.07.015
