CLINICAL HISTORY:

Signs and symptoms:  moderate pruritus

Previous Treatment:  Retin-A cream and cryosurgery

Other information:  He had been in a hot tub two weeks prior to the onset of his lesions. The suddenly appeared suddenly on his knees and elbows and subsequently spread to his abdomen, lower back, thighs and buttocks. He presented to the emergency department and was diagnosed with molluscum contagiosum. No other family members are affected. He has a history of diabetes mellitus type 2 and had not been on his medications for several months because of financial constraints. He denied having any nausea, vomiting or abdominal pain.

PHYSICAL EXAM:

The patient is a 40 year old 120kg Caucasian male with multiple 2-4mm yellow hard papules on his knees, thighs, buttocks, back, abdomen and elbows. Some have an erythematous halo in which the patient attributed to previous cryosurgery. The lesions did not exhibit any central umbilication or Koebner phenomenon. There was no evidence of Grey Turner’s sign or Cullen’s sign.

LABORATORY TESTS:

Glucose 339 mg/dL
Hemoglobin A1C 13.1%
Cholesterol 4,990 mg/dL
Triglycerides >5,750 mg/dL
HDL 12 mg/dL
LDL *
VLDL *
Blood was grossly lipemic.
*Calculations for LDL and VLDL are not accurate when triglycerides are >400.

DERMATOHISTOPATHOLOGY:

Microscopic description: The epidermis is unremarkable. Foamy histiocytes are noted throughout the reticular dermis. There is a mixed inflammatory infiltrate present containing neutrophils and lymphocytes. Extracellular lipid depositions that are seen as artifactual clefts filled with a wispy faint blue-gray material are also present in the dermis.

DIFFERENTIAL DIAGNOSIS:

1.   Eruptive histiocytomas
2.   Granuloma annulare
3.   Juvenile xanthogranulomas
4.   Eruptive xanthomas
5.   Molluscum contagiosum

SCROLL DOWN FOR ANSWER AND DISCUSSION.

CORRECT DIAGNOSIS:

Eruptive xanthomas

DISCUSSION:

Cutaneous xanthomas are localized infiltrates of lipid containing foamy macrophages located in the dermis and tendons. They are a marker of underlying abnormal lipoprotein metabolism, with the potential sequelae of atherosclerotic vascular disease, pancreatitis and death. The classification of the different types of cutaneous xanthomas are summarized on Table I. Patients with eruptive xanthomas often have triglyceride levels exceeding 3000-4000 mg/dl. Genetic deficiency of lipoprotein lipase, familial deficiency of apoprotein CII, endogenous familial hypertriglyceridemia, and medicine induced elevations of triglycerides are all possible causes. Underlying medical conditions such as diabetes mellitus, hypothyroidism, renal failure, pancreatitis, obesity and treatment with estrogens, isotretinoin, acitretin, and corticosteroids may also contribute to hypertriglyceridemia.

In North America, over 100 million people suffer from hypercholesterolemia. Despite this large number, most people with hypercholesterolemia and hypertriglyceridemia do not develop xanthomas. The exact mechanism of the formation of cutaneous xanthomas is not known. However a possible explanation is the permeation of circulating plasma lipoproteins through dermal capillary vessels into the dermis or tendons. Subsequently, macrophages phagocytize these lipoproteins forming the classic histiologic findings of foamy histiocytic cells.

Clinical features of eruptive xanthomas are characterized by yellowish papules measuring approximately 1-4mm in diameter. They are predominantly located over the extensor surfaces of the extremities, buttocks, and hands. However, the lesions can involve the trunk. An inflammatory halo may be seen in early lesions. This is thought to be due to the triglyceride component and may attribute to the tenderness and pruritus experienced by the patient. Furthermore, the Koebner’s phenomenon has been reported to occur in eruptive xanthomas.

TREATMENT:

Actual treatment for this patient:

Upon discussion of this patient with his internist, it was decided to admit him to the hospital for appropriate workup and initiation of lipid lowering medication.


Other Treatment options:

Control of the underlying hyperlipidemia or hyperglycemic state results in complete resolution of the lesions. Workup should include identification of familial hyperlipoproteinemias; the most common being Frederickson type IV & V, dysfunctional apoprotein C-II, lipoprotein lipase deficiency, or impaired insulin activity.
Obesity, high caloric intake, diabetes mellitus, alcohol abuse, estrogen replacement and retinoid therapy can exacerbate genetic defects of triglyceride metabolism and should be addressed. Complications of missed diagnosis can result in pancreatitis or atherosclerosis.

REFERENCES:

1. McKee PH, Marsden RA, Santa Cruz DJ. Pathology of the Skin with Clinical Correlations. Times Mirror International Publishers Limited. 1997; 7.3-7.5.

2. Bolognia, J.L., Jorizzo, J.L., Rapini, R.P., et al. Dermatology. 2003,Elsevier. Volume II pp 1447-1454.

3. Odom, R.B., James, W.D., Berger, T.M. Andrew’s Diseases of the Skin: Clinical dermatology 9th edition. Pp 664-665

4. Arndt, K.A., Leboit, P.E., Robinson, J.K., Wintroub, B.U. et al. Cutaneous Medicine and Surgery: An integrated program in dermatology Volume II p. 1809

Additional Comment:

© Copyright 2003-2006 by AOCD Grand Rounds

Top of Page