Condylomas and warts can clinically resemble seborrheic keratoses, and dermatoscopy can be helpful. On the penis and genital skin, condylomas and seborrheic keratoses can be difficult to differentiate, even on biopsy.A study examining over 4,000 biopsied skin lesions identified as seborrheic keratoses showed 3.1% were malignancies. Two thirds of those were squamous cell carcinoma. To date, the gold standard in the diagnosis of seborrheic keratosis is represented by the histolopathologic analysis of a skin biopsy. Subtypes
Seborrheic keratoses may be divided into the following types:

Main differential diagnoses
Dermatosis papulosa nigra (DPN) is a condition of many small, benign skin lesions on the face, a condition generally presenting on dark-skinned individuals. : 638–9  DPN is extremely common, affecting up to 30% of Black people in the US. Treatment
No treatment of seborrheic keratoses is necessary, except for aesthetic reasons. Generally, lesions can be treated with electrodesiccation and curettage, or cryosurgery. When correctly performed, removal of seborrheic keratoses will not cause much visible scarring. Epidemiology
Seborrheic keratosis is the most common benign skin tumor. Incidence increases with age. There is less prevalence in people with darker skin. In large-cohort studies, 100% of the patients over age 50 had at least one seborrheic keratosis. Onset is usually in middle age, although they are common in younger patients too—found in 12% of 15-year-olds to 25-year-olds—making the term "senile keratosis" a misnomer. See also
The sign of Leser-Trélat

Notes
References
External links

DermAtlas 185
Fitz-Hugh–Curtis syndrome is a rare complication of pelvic inflammatory disease (PID) involving liver capsule inflammation leading to the creation of adhesions. The condition is named after the two physicians, Thomas Fitz-Hugh, Jr and Arthur Hale Curtis who first reported this condition in 1934 and 1930 respectively. Signs and symptoms
The major symptom and signs include an acute onset of right upper quadrant (RUQ) abdominal pain aggravated by breathing, coughing or laughing, which may be referred to the right shoulder. There is usually also tenderness on palpation of the right upper abdomen and tenderness to percussion of the lower ribs which protect the liver. Surprisingly there is often no or only minimal pelvic pain, vaginal discharge or cervical motion tenderness, which may lead to the diagnosis being missed. This may be due to infectious bacteria bypassing pelvic structures on the way to the liver capsule. Pathophysiology
Fitz-Hugh–Curtis syndrome occurs almost exclusively in women. It is usually caused by Chlamydia trachomatis (Chlamydia) or Neisseria gonorrhoeae (Gonorrhea) though other bacteria such as Bacteroides, Gardnerella, E. coli and Streptococcus have also been found to cause Fitz-Hugh-Curtis syndrome on occasion. These bacterial pathogens  cause a thinning of cervical mucus and allow bacteria from the vagina into the uterus and fallopian tubes, causing infection and inflammation. Occasionally, this inflammation can cause scar tissue to form on Glissons capsule, a thin layer of connective tissue surrounding the liver. (Bailey&Love)

Diagnosis
Abdominal ultrasound will typically be normal.