Differential Diagnosis for Follicular Acne on Chest, Shoulders, and Back
Single Most Likely Diagnosis
- Acne Vulgaris: This is the most common form of acne and can occur on the face, chest, shoulders, and back. The presence of follicular acne in these areas is consistent with acne vulgaris, which is often triggered by hormonal changes, stress, and genetics.
Other Likely Diagnoses
- Folliculitis: An inflammatory condition of the hair follicles, which can be caused by bacterial, viral, or fungal infections. It presents similarly to acne but is typically more painful and may be accompanied by signs of infection.
- Keratosis Pilaris: A condition characterized by the formation of small, rough bumps on the skin due to the accumulation of keratin, a protein that protects the skin. While it doesn't typically present as follicular acne, it can cause rough skin texture that might be confused with acne in some cases.
- Pityrosporum Folliculitis: A type of folliculitis caused by the yeast Pityrosporum ovale (now known as Malassezia), which is naturally found on the skin. It can cause acne-like eruptions, particularly on the chest and back.
Do Not Miss Diagnoses
- Steroid-Induced Acne: The use of systemic or topical corticosteroids can lead to acne-like eruptions. This diagnosis is crucial because it implies a need to reassess the patient's medication regimen.
- Hidradenitis Suppurativa: A chronic skin condition characterized by recurrent, painful abscesses and nodules in the apocrine-gland-bearing areas of the body, such as the axillae and groin. While it doesn't typically present as follicular acne, it can cause significant morbidity if not recognized and treated appropriately.
Rare Diagnoses
- Gonadal or Adrenal Tumors: Rarely, acne can be a symptom of underlying hormonal imbalances caused by tumors of the gonads or adrenal glands. These conditions would require immediate medical attention due to their potential for serious health consequences.
- Congenital Adrenal Hyperplasia: A group of inherited disorders that affect the adrenal glands, leading to hormone imbalances. Acne can be one of the presenting symptoms, particularly in cases of 21-hydroxylase deficiency.
- Apert Syndrome: A rare genetic disorder characterized by premature fusion of the bones of the skull, which can also include acne-like skin lesions among its symptoms.