Related Experiment Video
Updated: Jul 18, 2025
05:38
Dermoscopy Aids in the Diagnosis of Discoid Lupus Erythematosus
Published on: May 16, 2025
121
Reverse Koebner phenomenon in erythema nodosum leprosum
Sukhdeep Singh1, Tarun Narang1, Sunil Dogra1
1Department of Dermatology, Venereology and Leprology, Post Graduate Institute of Medical Education and Research, Chandigarh, India160012.
Summary
Erythema nodosum leprosum (ENL) can exhibit a reverse Koebner phenomenon, where new lesions avoid previous scar sites. This study describes this unique presentation in a leprosy patient, highlighting immune-mediated skin sparing.
Area of Science:
- Dermatology
- Immunology
- Infectious Diseases
Background:
- Erythema nodosum leprosum (ENL) is an immune-mediated complication of leprosy.
- The reverse Koebner phenomenon describes the sparing of prior injury sites by new dermatological lesions.
- This phenomenon has been observed in various skin conditions but not previously documented in ENL.
Purpose of the Study:
- To report and analyze a case of erythema nodosum leprosum exhibiting the reverse Koebner phenomenon.
- To investigate the potential immunological basis for skin lesion sparing in ENL.
Main Methods:
- Case presentation of a middle-aged woman with lepromatous leprosy.
- Clinical observation and documentation of skin lesions, noting their distribution relative to previous scars.
Main Results:
- The patient presented with painful, reddish nodules characteristic of ENL.
- New ENL lesions distinctly spared areas of previous scarring.
- This observation represents the first documented instance of reverse Koebner phenomenon in ENL.
Conclusions:
- The observed sparing of scar sites in ENL is attributed to the reverse Koebner phenomenon.
- This suggests a localized immune resistance at previous injury sites in ENL.
- Further research is warranted to elucidate the mechanisms behind this phenomenon in leprosy.
Related Concept Videos
01:25Endocarditis II: Clinical Features of Infective Endocarditis
14
Endocarditis can present various clinical features depending on the causative organism and the patient's underlying health conditions. Initially, the clinical features of infective endocarditis develop gradually, presenting with nonspecific symptoms that can be easily mistaken for other illnesses.General SymptomsEarly symptoms of infective endocarditis are fever, chills, weakness, malaise, fatigue, and weight loss. These symptoms reflect the systemic nature of the infection and the body's...
14
01:15Reticular Dermis
2.6K
The papillary and reticular dermis are the two layers of the dermis. They are made of connective tissue with fibers of collagen extending from one to the other, making the border between the two somewhat indistinct. The dermal papillae extending into the epidermis belong to the papillary layer, whereas the dense collagen fiber bundles below belong to the reticular layer.
Reticular Layer
Underlying the papillary layer is the much thicker reticular layer, composed of dense, irregular connective...
Reticular Layer
Underlying the papillary layer is the much thicker reticular layer, composed of dense, irregular connective...
2.6K
01:14Changes in Skin Color: Clinical Perspectives
2.0K
The first thing a clinician sees is the skin, so the examination of the skin should be part of any thorough physical examination. Most skin disorders are relatively benign, but a few, including melanomas, can be fatal if untreated. A couple of the more noticeable disorders, albinism and vitiligo, affect the appearance of the skin and its accessory organs.
Albinism
Albinism is a genetic disorder that affects (completely or partially) the coloring of skin, hair, and eyes. The defect is primarily...
Albinism
Albinism is a genetic disorder that affects (completely or partially) the coloring of skin, hair, and eyes. The defect is primarily...
2.0K
01:30Skin Cancer
4.2K
Skin cancer is a type of cancer that occurs when there is an abnormal growth of skin cells, usually triggered by damage to the DNA within the skin cells. It is primarily caused by exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds. Skin cancer is the most common type of cancer worldwide, and its incidence continues to rise.
Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...
Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...
4.2K
01:11Papillary Dermis
3.0K
Dermis
The dermis might be considered the "core" of the integumentary system, as distinct from the epidermis and hypodermis. It contains blood and lymph vessels, nerves, and other structures, such as hair follicles and sweat glands. The dermis is made of two layers of connective tissue that comprise an interconnected mesh of elastin and collagenous fibers, produced by fibroblasts.
Papillary Layer
The papillary layer is made of loose, areolar connective tissue, which means the collagen...
The dermis might be considered the "core" of the integumentary system, as distinct from the epidermis and hypodermis. It contains blood and lymph vessels, nerves, and other structures, such as hair follicles and sweat glands. The dermis is made of two layers of connective tissue that comprise an interconnected mesh of elastin and collagenous fibers, produced by fibroblasts.
Papillary Layer
The papillary layer is made of loose, areolar connective tissue, which means the collagen...
3.0K
01:24Nephrotic Syndrome I : Introduction
9
Nephrotic Syndrome is a chronic kidney disorder defined by clinical findings such as severe proteinuria, hypoalbuminemia, hyperlipidemia, and edema. These symptoms result from damage to the glomeruli, the kidney’s filtering units, increasing their permeability to proteins.Definition and Meaning:Proteinuria, defined as the loss of more than 3.5 grams of protein per day in adults, is a crucial feature of nephrotic syndrome. This condition is often accompanied by edema, the accumulation of...
9