open access

Vol 48, No 3 (2010)
ORIGINAL PAPERS
Published online: 2010-11-13
Submitted: 2011-12-19
Get Citation

Type II muscle fibers atrophy associated with silent corticotroph adenoma in a dog.

F Trapani, M L Del Basso De Caro, L Insabato, S Papparella, O Paciello
DOI: 10.2478/v10042-010-0038-7
·
Folia Histochem Cytobiol 2010;48(3):403-406.

open access

Vol 48, No 3 (2010)
ORIGINAL PAPERS
Published online: 2010-11-13
Submitted: 2011-12-19

Abstract

The Silent Corticotroph Adenoma (SCA) is a pituitary adenoma variant characterized by the immunoreactivity for adrenocorticotropic hormone (ACTH) and related peptides, without the clinical signs of Cushing's disease. SCA has been postulated to either secrete structurally abnormal ACTH that is inactive but detectable by immunohistochemistry or radioimmunoassay, or to secrete ACTH intermittently or at low levels continuously. Excess of ACTH has been associated to type II muscle atrophy. We describe a case of type II muscle fibers atrophy associated with silent corticotroph adenoma in a dog. The dog showed moderate to severe proximal muscle wasting and weakness with normal levels of muscle-associated enzymes. In the limb muscle biopsies, type II fibers were uniformly smaller than type I fibers. In temporalis muscles, there were few atrophic fibers, and several irregular areas of loss of enzymatic activity observed in NADH, SDH and COX stains. The tumour showed a trabecular growth pattern and immunohistochemical analysis demonstrated the presence of cytoplasmic immunoreactivity for ACTH. The muscle atrophy was considered to be related to an excess of inactive ACTH. Studying spontaneous occurring rare diseases in animals could help to understand the mechanism of similar diseases in human has well.

Abstract

The Silent Corticotroph Adenoma (SCA) is a pituitary adenoma variant characterized by the immunoreactivity for adrenocorticotropic hormone (ACTH) and related peptides, without the clinical signs of Cushing's disease. SCA has been postulated to either secrete structurally abnormal ACTH that is inactive but detectable by immunohistochemistry or radioimmunoassay, or to secrete ACTH intermittently or at low levels continuously. Excess of ACTH has been associated to type II muscle atrophy. We describe a case of type II muscle fibers atrophy associated with silent corticotroph adenoma in a dog. The dog showed moderate to severe proximal muscle wasting and weakness with normal levels of muscle-associated enzymes. In the limb muscle biopsies, type II fibers were uniformly smaller than type I fibers. In temporalis muscles, there were few atrophic fibers, and several irregular areas of loss of enzymatic activity observed in NADH, SDH and COX stains. The tumour showed a trabecular growth pattern and immunohistochemical analysis demonstrated the presence of cytoplasmic immunoreactivity for ACTH. The muscle atrophy was considered to be related to an excess of inactive ACTH. Studying spontaneous occurring rare diseases in animals could help to understand the mechanism of similar diseases in human has well.
Get Citation
About this article
Title

Type II muscle fibers atrophy associated with silent corticotroph adenoma in a dog.

Journal

Folia Histochemica et Cytobiologica

Issue

Vol 48, No 3 (2010)

Pages

403-406

Published online

2010-11-13

DOI

10.2478/v10042-010-0038-7

Bibliographic record

Folia Histochem Cytobiol 2010;48(3):403-406.

Authors

F Trapani
M L Del Basso De Caro
L Insabato
S Papparella
O Paciello

Important: This website uses cookies. More >>

The cookies allow us to identify your computer and find out details about your last visit. They remembering whether you've visited the site before, so that you remain logged in - or to help us work out how many new website visitors we get each month. Most internet browsers accept cookies automatically, but you can change the settings of your browser to erase cookies or prevent automatic acceptance if you prefer.

By "Via Medica sp. z o.o." sp.k., ul. Świętokrzyska 73, 80–180 Gdańsk

tel.:+48 58 320 94 94, faks:+48 58 320 94 60, e-mail:  viamedica@viamedica.pl