Ridley-Jopling Classification (Leprosy Spectrum)
The Ridley-Jopling classification of leprosy (Ridley and Jopling 1966): a five-group SPECTRUM ordered by cell-mediated immune response, not a ladder of severity.
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Example
- The Ridley-Jopling group
- I
Result: Indeterminate leprosy, outside the five-group spectrum.
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What the result means
- TT
- Tuberculoid. High resistance, few asymmetric lesions, lepromin positive, epithelioid granulomas reaching the epidermis.
- BT
- Borderline tuberculoid. Lepromin positive, asymmetric lesions with satellites, several nerves thickened.
- BB
- Mid-borderline. The least stable position on the spectrum; lepromin weak or absent.
- BL
- Borderline lepromatous. Many increasingly symmetric lesions, macrophage granulomas, widespread nerve thickening.
- LL
- Lepromatous. Little or no resistance, numerous symmetric lesions, lepromin absent, sheets of foamy macrophages.
- WHO crosswalk
- TT and BT are paucibacillary; BB, BL, and LL are multibacillary. Nerve involvement alone makes a case multibacillary today.
- Bacterial index
- No per-group value is given here: sources disagree. It is negative at the tuberculoid pole and highest at the lepromatous pole.
What you enter
- The Ridley-Jopling group.
Full field descriptions
- The Ridley-Jopling group. Requires the lepromin response and histology, not just the clinical picture [TT = TT (tuberculoid), High cell-mediated resistance. BT = BT (borderline tuberculoid), Substantial but incomplete resistance. BB = BB (mid-borderline), Unstable. This is the least stable position on the spectrum, and untreated cases tend to shift toward one pole. BL = BL (borderline lepromatous), Little resistance. LL = LL (lepromatous), Little or no cell-mediated resistance. I = Indeterminate, outside the five-group spectrum]
How this is calculated
Ridley DS, Jopling WH. Classification of leprosy according to immunity. A five-group system. Int J Lepr Other Mycobact Dis. 1966;34(3):255-273. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.