Bullous pemphigoid Lecture, Pathology, Treatment, Dermatology USMLE NEETPG

Summary

This video explains Bullous Pemphigoid, an autoimmune disorder where the body's immune system attacks hemidesmosomes, structures that anchor skin cells to the basement membrane. The destruction of hemidesmosomes causes skin detachment, leading to the formation of blisters. The video covers clinical signs, including thick-walled blisters with a negative Nikolsky sign, and differences between Bullous Pemphigoid and Pemphigus Vulgaris. Diagnosis is made through biopsy and immunofluorescence. Treatment typically involves glucocorticoids, and topical steroids may be used if no oral lesions are present. The video offers insights into the condition and its management.

Takeaways

• 😀 Bullous pemphigoid is an autoimmune disease where the immune system attacks hemidesmosomes, leading to skin detachment and blister formation.
• 😀 Hemidesmosomes are the structures that hold skin cells to the basement membrane. When destroyed, skin cells detach, forming blisters.
• 😀 Bullous pemphigoid typically affects elderly patients, especially those in their 70s and 80s, and can be drug-induced, often by sulfur-containing drugs.
• 😀 The blisters in bullous pemphigoid are thick-walled and less likely to rupture, making the Nikolsky sign negative, unlike in pemphigus vulgaris.
• 😀 Oral lesions are rare in bullous pemphigoid, unlike in pemphigus vulgaris, where oral lesions are common.
• 😀 Diagnosis of bullous pemphigoid can be confirmed through a biopsy and immunofluorescence staining, showing a linear pattern at the basement membrane.
• 😀 The Nikolski sign is negative in bullous pemphigoid because the blisters have thicker layers of skin compared to the fragile blisters in pemphigus vulgaris.
• 😀 Treatment of bullous pemphigoid often involves glucocorticoids to suppress the immune system. Topical steroids may be used if no oral lesions are present.
• 😀 Infection is less likely in bullous pemphigoid because the thick-walled blisters do not rupture easily, reducing exposure to bacteria.
• 😀 The key differences between bullous pemphigoid and pemphigus vulgaris include the age of onset, presence of oral lesions, and Nikolsky sign results.

Q & A

What is Bullous Pemphigoid?

Bullous Pemphigoid is an autoimmune disease where the body's immune system attacks hemidesmosomes, causing the skin cells to detach from the basement membrane and form blisters.

What role do hemidesmosomes play in skin structure?

Hemidesmosomes are structures that attach the skin cells to the basement membrane, acting as glue to hold the cells in place.

How does the immune response in Bullous Pemphigoid cause blister formation?

In Bullous Pemphigoid, antibodies target and destroy hemidesmosomes, leading to the detachment of skin cells from the basement membrane. The space between these layers fills with fluid, forming blisters.

What are the main differences between Bullous Pemphigoid and Pemphigus Vulgaris?

Bullous Pemphigoid mainly affects elderly people and has thick-walled blisters that are less likely to rupture, with a negative Nikolsky sign. In contrast, Pemphigus Vulgaris primarily affects younger individuals, with fragile blisters and a positive Nikolsky sign.

What is the Nikolsky sign, and how does it differ in Bullous Pemphigoid?

The Nikolsky sign refers to the skin's ability to easily detach when slightly touched. In Bullous Pemphigoid, the Nikolsky sign is negative because the blisters are thick-walled and not easily ruptured.

Are oral lesions common in Bullous Pemphigoid?

No, oral lesions are rare in Bullous Pemphigoid, unlike Pemphigus Vulgaris, where they are more common.

How is Bullous Pemphigoid diagnosed?

Bullous Pemphigoid is diagnosed through biopsy, where histological examination or immunofluorescence staining can reveal the destruction of hemidesmosomes and the characteristic linear pattern around the basement membrane.

What is immunofluorescence, and how is it used in the diagnosis of Bullous Pemphigoid?

Immunofluorescence is a diagnostic technique where a stain is applied that binds to antibodies attacking hemidesmosomes. This staining appears in a linear pattern around the basement membrane, indicating Bullous Pemphigoid.

What are the main treatment options for Bullous Pemphigoid?

The main treatment options for Bullous Pemphigoid are glucocorticoids (like prednisone) to suppress the immune system and topical steroids if no oral lesions are present. A combination of tetracycline, erythromycin, and nicotinamide can also be used.

Why are infections less common in Bullous Pemphigoid?

Infections are less common in Bullous Pemphigoid because the blisters have thick walls and do not rupture easily, reducing the risk of bacterial exposure.