ULAM IN-VIVO ANIMAL CORE

UNIVERSITY OF MICHIGAN

Main Laboratory
North Campus Research Complex
2800 Plymouth Rd., Bld. 36: G155/157
Ann Arbor, MI 48109-2800
(734) 647-0731

Satellite Location
3527 Animal Research Facility
1150 W. Medical Center Dr.
Ann Arbor, MI 48109-0614
(734) 936-3803

ulam-ivac@umich.edu

Case Information:

Necropsy Date:	12/14/23	Clinician:	Lester/Martin
IVAC Service ID:	23-3236	Prosector:	Hasler
Species:	ACC	Gross necropsy pathologist:	Lee
Principal Investigator:	Abdel-Latif	Other contact:	Suhan
Depart:

Animal ID:

Animal ID:	Clinical Number:	Age:	Sex:	Genotype/Strain/Study:	Mode of Death:
23x10879		2 weeks	M		Euthanized-Other

Clinical History:

Male spiny mouse pup born 11/25/23 presented with its left eye swollen shut on 12/6. Most of the swelling appeared to be underneath the eye. There was also a small skin lesion on the left muzzle. The eye was flushed with sterile saline and treated with neo-poly-bac eye ointment twice (12/6 and 12/8), and the pup received 3 doses of carprofen (12/6, 12/8, and 12/11). The eye did not improve and developed grey crusty discharge, so the pup was euthanized via isoflurane overdose followed by bilateral pneumothorax.

Final Diagnos(es) for Case

Organ/System	Process	Diagnosis
Special senses	Inflammatory	Blepharoconjunctivitis, sterile

Final Comments:

Inflammation involving the eyelid and conjunctiva was noted, but there was no clear evidence for any infectious etiology histologically. No neoplasia nor structural anomaly was found. Noninfectious blepharoconjunctivitis was suspected in this case. Such condition has been reported fairly frequently in aging 129 strain of mice, in which age-related structural and functional changes in the lacrimal glands might interfere mucocutaneous barrier function, leading to sterile blepharoconjunctivitis. Co-infection with bacteria is possible, but the bacteria usually were not the primary issue because these bacteria could also be isolated from healthy hosts. SPF housing may not prevent such spontaneous condition.

Pathologist Only:

Case Complete?	Yes
Final Review Pathologist:	Yao Lee, DVM, MS, PhD, DACVP
Completion Date:	2024-01-02

Gross Findings

Body condition score:	3/5
Carcass condition:	Intact
Autolysis:	None

Gross Lesions

Organ System	Evaluated? (Y/N/Some animals)	Findings or Comments Y/N	Comments (only if Findings)
Cardiovascular	Y	N
Endocrine	Y	N
Gastrointestinal	Y	N
Hematolymphoid	Y	N
Hepatic	Y	N
Integument	Y	N
Musculoskeletal	Y	N
Nervous	N	N	Head left intact in formalin so brain not examined.
Reproductive	Y	N
Respiratory	Y	N
Special senses	Y	Y	Periorbital swelling around the left eye. Left eye contained liquid grey discharge at the time of necropsy.
Urinary	Y	N

Additional Procedures Performed: Check all that apply

Tissues Frozen	Samples of liver, kidney, and spleen held back.
Tissues Refrigerated	Swab of left eye to send for culture.
Culture, left eye swab	Few Streptococcus suis

Microscopic Findings

Organ/Slide	Findings Y/N	Description
Adrenal Glands	N
Brain	N
Heart	N
Kidneys	N
Liver	N
Lungs	N
Salivary Glands	N
Skeletal muscle	N
Skull	Y	The epidermis of the eyelid is thickened by proliferation of the stratum spinosum and prominent rete ridges (acanthosis), covered by layers of keratin (orthokeratotic hyperkeratosis). The dermis and a lesser extent to epidermis are infiltrated with a small number of lymphocytes and fewer neutrophils. The epithelium of the cornea is slightly disorganized and hyperplastic.
Spleen	N
Sternum	N
Stomach and colon	N

Microscopic Morphologic Diagnos(es)

Organ/System	Process	Morphologic Diagnosis
Eye	Inflammatory	Blepharoconjunctivitis, focally extensive, subacute, moderate, with orthokeratotic hyperkeratosis