Acanthosis Nigricans

Abstract: 76 yo woman with 6 months history seen on July 25, 2007.
History: This elderly woman presented for progressive hyperpigmentation of skin folds (neck, axillae, groin, and inframammary folds). She felt she was in good general health, but noted some recent weight loss, "bloating" and scalp pruritus. She had a sister who died of pancreatic cancer.
O/E: Velvety gray-black hyperpigmentation of affected areas. In addition some she has some verrucous tumors on arms and legs.
Clinical Photo(s):




Lab: Ultrasound of abdomen showed ascites. Abdominal CT revealed "focal masses involving the omentum and peritoneal cavity most likely representing metastatic disease. Extensive ascites, hepatic custs and a left lower lobe nodule of uncertain significance. Exploratory lap found wide-spread metastatic disease, exact cell-type could not be determined.
Histopathology: N/A
Diagnosis: Malignant Acanthosis Nigricans.
Reason Presented: For interest.
Discussion:"The exact incidence of AN is unknown. In an unselected population of 1412 children, the changes of AN were present in 7.1%. Obesity is closely associated with AN, and more than one half of the adults who weigh greater than 200% of their ideal body weight have lesions consistent with AN. The malignant form of AN is far less common, and, in one study, only 2 of 12,000 patients with cancer had signs of AN.
Malignant AN is associated with significant complications because the underlying malignancy is often an aggressive tumor. Average survival time of patients with signs of malignant AN is 2 years, although cases in which patients have survived for up to 12 years have been reported. In older patients with new onset AN, most have an associated internal malignancy." (from eMedicine chapter)
Follow-up: The patient was seen back on April 18, 2008. She has had chemotherapy and is doing OK. She was again complaining about the hyperpigmentation. She looked pretty good; but understands she has metastatic disease of unknown origin. She was looking forward to going to Florida in a few weeks to visit a daughter. She would like the dark areas treated. Tretinoin may be of some value and will be tried when she returns. In the face of a grave prognosis she is a feisty septuagenarian with a smile and a sense of humor.
References: eMedicine Chapter on A.N.

Perplexing Dermatosis of Legs

Abstract: 33 year-old man with perplexing rash on legs and feet
Presented by Natasha Karishev and Dave Elpern

HPI: This 33-year old man was seen at the FMI on April 11, 2008. He has noticed an asymptomatic eruption on legs and feet for the past few months. He had Graves Disease treated over ten years ago and now is hypothyroid. In addition, he suffers with hypertension and bipolar disorder. His medications include: HCTZ , Depakote, Levothyroxine, Imipramine, Zolpidem, Caduet ((Amlodipine/Atorvastatin)

O/E: Both lower legs are covered with orange-brown, some rust-colored, speckled, cayenne pepper–like discoloration. Spared area under socks. The “Cayenne Pepper-Like” spots are punctate areas of hemorrhage. The patient has exophthalmos, a residual effect of his past Grave’s disease.

Photos: Click on image to enlarge



Diagnosis: Pigmented Purpuric Dermatosis: Subtype: Schamberg Disease

Reason Presented: As a teaching opportunity re: an easily recognized entity that can be misdiagnosed if not known about. This is what is called “A Dermatologic Vignette.”

Discussion: From eMedicine: “The pigmented purpuric dermatoses are a group of chronic diseases of mostly unknown etiology that have a very distinctive clinical appearance. They are characterized by extravasation of erythrocytes in the skin with marked hemosiderin deposition. The etiology is unknown. Venous hypertension, exercise, and gravitational dependency are important cofactors that appear to influence disease presentation. No medical intervention is of proven benefit for the treatment of the pigmented purpuric dermatoses.
* If pruritic use topical corticosteroids and antihistamines.
* Associated venous stasis should be treated by compression stockings.
* Prolonged leg dependency should be avoided.”

In the present case, it is likely that his drugs are playing a role. These may lead to venous hypertension and resulting leakage of rbc. There are old reports of HCTZ causing PPD. The clear areas under his socks indicate that compression stockings may be the best approach here. It is thought that PPDs are caused by capillaritis which leads to leaky vessels. The extravasated RBCs are red (Cayenne Pepper Spots) and when these are reabsorbed they leave hemosiderin behing (the golden brown rusty color)

Reference: The chapter on PPD in eMedicine is an adequate introduction: