Pre Lecture Dermatology. 2026. Prof. Lavandera x R. Marzo
Question 1
A male patient presents with a tender, well-outlined, bright, red-colored plaque on his nose.
He denies shortness of breath or changes in voice quality. You highly suspect which of the
following?
a. Cellulitis
b. Angioedema
c. Herpes zoster
d. Erysipelas
✅ Correct Answer
✔ D. Erysipelas
📚 FNP Board Review
Erysipelas es una infección bacteriana superficial de la dermis y los vasos linfáticos, casi
siempre causada por Group A β-hemolytic Streptococcus (Streptococcus pyogenes).
La localización más frecuente es:
Face (nose, auricles, cheeks)
Lower extremities
La clave del Board es que produce una lesión:
Bright red
Raised plaque
Well-demarcated borders
Dolorosa
Analizando cada opción
A. Cellulitis
❌ Incorrecta
La Cellulitis afecta la deep dermis y el subcutaneous tissue.
Características:
, Borders poorly defined
Flat lesion
Diffuse erythema
Usually caused by Strep o Staphylococcus aureus
👉 Board Pearl
Cellulitis = poorly demarcated
B. Angioedema
❌ Incorrecta
Produce:
Rapid swelling
Lips
Tongue
Face
Airway compromise
En la pregunta el paciente niega voice changes y shortness of breath, lo cual prácticamente
descarta angioedema.
C. Herpes Zoster
❌ Incorrecta
Produce:
Painful vesicular rash
Dermatomal distribution
Burning pain
Vesicles
No una placa eritematosa bien delimitada.
D. Erysipelas
✅ Correcta
Características clásicas:
Bright red plaque Tender
Raised borders Fever frecuente
Well-demarcated lesion
, Face (especialmente nariz, orejas y
mejillas)
Agente más común:
Streptococcus pyogenes
High-Yield Comparison
Erysipelas Cellulitis
Superficial dermis Deep dermis/subcutaneous tissue
Raised plaque Flat erythema
Well-demarcated Poorly demarcated
Bright red Diffuse red
Usually Streptococcus Streptococcus or Staphylococcus
, Treatment
Mild disease:
Penicillin
Amoxicillin
Cephalexin
Severe disease:
IV Cefazolin
IV Penicillin G
MRSA risk:
Clindamycin
TMP-SMX + beta-lactam
Doxycycline + beta-lactam
🚀 Exam Pearls
Raised + bright red + sharply demarcated = Erysipelas.
Poorly demarcated = Cellulitis.
Face involvement es extremadamente típico de Erysipelas.
Most common organism: Streptococcus pyogenes.
Question 1
A male patient presents with a tender, well-outlined, bright, red-colored plaque on his nose.
He denies shortness of breath or changes in voice quality. You highly suspect which of the
following?
a. Cellulitis
b. Angioedema
c. Herpes zoster
d. Erysipelas
✅ Correct Answer
✔ D. Erysipelas
📚 FNP Board Review
Erysipelas es una infección bacteriana superficial de la dermis y los vasos linfáticos, casi
siempre causada por Group A β-hemolytic Streptococcus (Streptococcus pyogenes).
La localización más frecuente es:
Face (nose, auricles, cheeks)
Lower extremities
La clave del Board es que produce una lesión:
Bright red
Raised plaque
Well-demarcated borders
Dolorosa
Analizando cada opción
A. Cellulitis
❌ Incorrecta
La Cellulitis afecta la deep dermis y el subcutaneous tissue.
Características:
, Borders poorly defined
Flat lesion
Diffuse erythema
Usually caused by Strep o Staphylococcus aureus
👉 Board Pearl
Cellulitis = poorly demarcated
B. Angioedema
❌ Incorrecta
Produce:
Rapid swelling
Lips
Tongue
Face
Airway compromise
En la pregunta el paciente niega voice changes y shortness of breath, lo cual prácticamente
descarta angioedema.
C. Herpes Zoster
❌ Incorrecta
Produce:
Painful vesicular rash
Dermatomal distribution
Burning pain
Vesicles
No una placa eritematosa bien delimitada.
D. Erysipelas
✅ Correcta
Características clásicas:
Bright red plaque Tender
Raised borders Fever frecuente
Well-demarcated lesion
, Face (especialmente nariz, orejas y
mejillas)
Agente más común:
Streptococcus pyogenes
High-Yield Comparison
Erysipelas Cellulitis
Superficial dermis Deep dermis/subcutaneous tissue
Raised plaque Flat erythema
Well-demarcated Poorly demarcated
Bright red Diffuse red
Usually Streptococcus Streptococcus or Staphylococcus
, Treatment
Mild disease:
Penicillin
Amoxicillin
Cephalexin
Severe disease:
IV Cefazolin
IV Penicillin G
MRSA risk:
Clindamycin
TMP-SMX + beta-lactam
Doxycycline + beta-lactam
🚀 Exam Pearls
Raised + bright red + sharply demarcated = Erysipelas.
Poorly demarcated = Cellulitis.
Face involvement es extremadamente típico de Erysipelas.
Most common organism: Streptococcus pyogenes.
