Nail Psoriasis Severity Index (NAPSI)

DESCRIPTION:
The Nail Psoriasis Severity Index scale is a simple, reproducible, and objective measure used to evaluate the severity of nail bed psoriasis and nail matrix psoriasis by area of involvement in the nail unit.¹

DISEASE STATES: 
Psoriasis

VALIDATED USES: 
Clinical trials, guiding medical therapy

ADMINISTRATION METHOD:
Physician, clinician, HCP representative

COMMONLY USED IN:
Clinical trials, clinical practice

DETAILED DESCRIPTION:
Each nail is divided into quadrants with imaginary horizontal and longitudinal lines. The physician, clinician, or an appropriate HCP representative examines each quadrant for clinical features of nail psoriasis:¹

• Nail matrix: pitting, leukonychia, red spots in the lunula, nail plate crumbling
• Nail bed: onycholysis, oil-drop dyschromia, subungual hyperkeratosis

NAPSI SCORING 

The sum of the nail matrix and nail bed scores is the total score for that nail. The highest possible score for each fingernail is 8 (4 for bed; 4 for matrix). All of the fingernail scores are added together for the total NAPSI score, which ranges from 0 to 80. Toenail scores are assessed in a similar fashion. If toenail scores are included, the total NAPSI score doubles, ranging from 0 to 160.¹

VALIDITY:
A positive correlation between NAPSI, Psoriasis Area Severity Index (PASI), and Dermatology Life Quality Index (DLQI) has been observed.⁶ Arif A et al. 2021 demonstrated a significant moderate positive correlation between NAPSI and Nail Psoriasis Quality of Life (NPQ10) (r=0.632, p=0.001).⁷ Aktan S et al. 2007 found good interrater reliability, intraclass correlation coefficient for total NAPSI score (0.649).⁸

LIMITATIONS:
NAPSI may lack the ability to detect change over time.⁹ There is potential for observers to miss de novo lesions on initially healthy nails after treatment begins, especially when  patients are seen by different observers. The scoring for nail-bed features appeared more reliable than scoring for nail-matrix features.⁷

This resource is intended for educational purposes only and is intended for US healthcare professionals. Healthcare professionals should use independent medical judgment. All decisions regarding patient care must be handled by a healthcare professional and be made based on the unique needs of each patient.

References: 1. Rich P, Scher RK. Nail Psoriasis Severity Index: a useful tool for evaluation of nail psoriasis. J Am Acad Dermatol. 2003;49(2):206-212. doi:10.1067/s0190-9622(03)00910-1. 2. Rigopoulos D, Gregoriou S, Makris M, Ioannides D. Efficacy of ustekinumab in nail psoriasis and improvement in nail-associated quality of life in a population treated with ustekinumab for cutaneous psoriasis: an open prospective unblinded study. Dermatology. 2011;223(4):325-329. doi:10.1159/000334482. 3. Tosti A, Ricotti C, Romanelli P, Cameli N, Paraccini BM. Evaluation of the efficacy of acitretin therapy for nail psoriasis. Arch Dermatol. 2009;145(3):269-271. doi:10.1001/archdermatol.2008.600 4. Bianchi L, Bergamin A, de Felice C, Capriotti E, Chimenti S. Remission and time of resolution of nail psoriasis during infliximab therapy. J Am Acad Dermatol. 2005;52(4):736-737. doi:10.1016/j.jaad.2004.09.012 5. Bardazzi F, Antonucci VA, Tengattini V, Odorici G, Balestri R, Patrizi A. A 36-week retrospective open trial comparing the efficacy of biological therapies in nail psoriasis. J Dtsch Dermatol Ges. 2013;11(11):1065-1070. doi:10.1111/ddg.12173 6. Prevezas C, Katoulis AC, Papadavid E, Panagakis P, Rigopoulos D. Short-term correlation of the Psoriasis Area Severity Index, the Nail Psoriasis Area Severity Index, and the Dermatology Life Quality Index, before and after treatment, in patients with skin and nail psoriasis. Skin Appendage Disord. 2019;5(6):344-349. doi:10.1159/000499348 7. Arif A, Mahadi IDR, Yosi A. Correlation between nail psoriasis severity index score with quality of life in nail psoriasis. Bali Med J. 2021;10(1): 256-260. doi:10.15562/bmj.v10i1.2198 8. Aktan S, Ilknur T, Akin C, Ozkan S. Interobserver reliability of the Nail Psoriasis Severity Index. Clin Exp Dermatol. 2007;32(2):141-144. doi:10.1111/j.1365-2230.2006.02305.x 9. Mease PJ. Measures of psoriatic arthritis: Tender and Swollen Joint Assessment, Psoriasis Area and Severity Index (PASI), Nail Psoriasis Severity Index (NAPSI), Modified Nail Psoriasis Severity Index (mNAPSI), Mander/Newcastle Enthesitis Index (MEI), Leeds Enthesitis Index (LEI), Spondyloarthritis Research Consortium of Canada (SPARCC), Maastricht Ankylosing Spondylitis Enthesis Score (MASES), Leeds Dactylitis Index (LDI), Patient Global for Psoriatic Arthritis, Dermatology Life Quality Index (DLQI), Psoriatic Arthritis Quality of Life (PsAQOL), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), Psoriatic Arthritis Response Criteria (PsARC), Psoriatic Arthritis Joint Activity Index (PsAJAI), Disease Activity in Psoriatic Arthritis (DAPSA), and Composite Psoriatic Disease Activity Index (CPDAI). Arthritis Care & Research. 2011;63(suppl 11):S64-S85. doi:10.1002/acr.20577