47-year-old male with anosacral plaque
Ahmed K. Alomari MD
Ian A. Gelarden BS
A previously healthy 47-year-old male truck driver presents with an irritated, irregular, brownish-gray plaque on the sacrum and intergluteal cleft. The H&E stain is shown below (Figure 1-3).
What is the best diagnosis?
Lichen amyloidosis
Lichen planus
Lichen simplex chronicus
Postinflammatory melanosis
Systemic amyloidosis
Which of the following is most likely to confirm the diagnosis?
Alkaline Congo red stain
Congo red stain (Highman modification)
Crystal violet stain
Cytokeratin LP34
Pagoda Red No. 9
Apaydin R, Gurbuz Y, Bayramgurler D, Muezzinoglu B, Bilen N. Cytokeratin expression in lichen amyloidosis and macular amyloidosis. JEADV 2004; 18:305-309.
Cheung ST, Mabesbwari MB, Tan CY. A comparative study of two Congo red stains for the detection of primary cutaneous amyloidosis. J Am Acad Dermatol 2006; 55: 363-364.
Huilgol SC; Ramnarain N; Carrington P; Leigh IM; Black MM. Cytokeratins in primary cutaneous amyloidosis. Australas J Dermatol. 1998; 39[2]: B1-5.
Klatskin G. Nonspecific green birefringence in congo red-stained tissues. The American Journal of Pathology. 1969; 56: 1-13.
Yanagihara M, Mehregan AH, Mehregan DR. Staining of amyloid with cotton dyes. Arch Dermatol. 1984; 120: 1184-1185.
Author Profiles
Ahmed K. Alomari
Indiana University, School of Medicine
Ahmed K. Alomari, MD, is an attending dermatopathologist and an assistant professor at Indiana University. He finished his AP/CP residency at Yale University and his dermatopathology fellowship at the University of Michigan.
Ian A. Gelarden
Indiana University, School of Medicine
Ian A. Gelarden is a fourth year medical student at Indiana University pursuing a career in pathology. He completed his BS in biology at Indiana University in Bloomington.
