Results
AFIP Wednesday Slide Conference - No. 30
May 12, 1999
- Conference Moderator: LTC Thomas P. Lipscomb
Division of Veterinary Pathology
Armed Forces Institute of Pathology
Washington DC 20306-6000
-
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Case I - E98-127 (AFIP 2638228)
- Signalment: Adult Holstein cow.
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- History: The lungs were harvested from an adult Holstein
cow at a slaughter house.
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- Gross Pathology: Close examination of the lungs revealed
small grey spots in many of the lobules. Several pulmonary arteries
contained variably-sized, non-adherent, soft, white-grey material.
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- Laboratory Results: None.
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- Contributor's Diagnoses and Comments:
- 1. Bronchiolitis, severe, multifocal, chronic, nonsuppurative
with bronchiolar smooth muscle hyperplasia (Bovine Farmer's Lung;
extrinsic allergic alveolitis).
2. Pulmonary embolization of brain tissue.
-
- Bovine farmer's lung (extrinsic allergic alveolitis) is a
disease primarily of adult cattle in areas with wet summers and
severe winters leading to a combination of moldy hay and housing
of cattle in winter. Baling or stacking high moisture hay (>30%)
results in overheating and proliferation of thermophilic molds
such as Micropolyspora faeni and Thermoactinomyces vulgaris.
Billions of spores and the metabolic products of these molds
are released when the hay is distributed during feeding. Inhalation
of spores by previously exposed animals results in activation
of both humoral and cellular immune effector functions resulting
in allergic reactions. The hypersensitivity response leads to
widespread infiltration of interalveolar septa by lymphocytes
and plasma cells. Extensive peribronchial accumulations of lymphocytes,
plasma cells, histiocytes, and smaller numbers of eosinophils
are accompanied by bronchiolar smooth muscle hypertrophy. Interstitial
epithelioid granulomas, an important diagnostic feature, may
be absent unless there has been recent antigenic exposure. These
lungs were harvested in late spring, presumably after the cows
had been turned out from the barn, which likely accounts for
the lack of granulomas.
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- Humane euthanasia in slaughter plants involves various methods
of stunning to render an animal insensible followed by exsanguination.2
A pneumatic-actuated penetrating captive bolt gun was used to
stun this animal. While the bolt is in the cranial cavity, injected
air disrupts the brain structure. Momentary severe increases
in intracranial pressure and simultaneous rupture of dural venous
sinuses or the development of a large cerebral venous defect
likely allows lacerated brain tissue to enter the venous system.
Brain emboli can lodge in various organs such as in pulmonary
arteries in the lung, as in this case, or in the liver, presumably
due to retrograde travel through the posterior vena cava.
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- AFIP Diagnoses:
- 1. Lung: Bronchitis and bronchiolitis, chronic and active,
lymphoplasmacytic and eosinophilic, multifocal, moderate, with
peribronchial and peribronchiolar lymphoid follicles, chronic
interstitial pneumonia, peribronchiolar and interstitial fibrosis,
and bronchiolitis obliterans, Holstein, bovine.
2. Lung, pulmonary artery: Brain embolus.
Note: Not all sections contain embolized brain in the
pulmonary artery.
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- Conference Note: Inflammatory cells expand peribronchial
and peribronchiolar interstitium, multifocally compress bronchiolar
lumens and extend into adjacent alveolar septa. Inflammatory
cells include lymphocytes, plasma cells, macrophages, and eosinophils.
The walls of several bronchioles are expanded by eosinophilic
fibrillar material, which occasionally extends into airway lumens.
Participants interpreted this material as fibrous connective
tissue; a Masson's trichrome stained the material blue confirming
this interpretation. The lumens of some bronchioles contain
mucin, eosinophils, neutrophils and macrophages. In some sections,
globule leukocytes and eosinophils are present within the epithelium
of larger bronchioles and bronchi.
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- This case was reviewed by the Department of Pulmonary and
Mediastinal Pathology. They interpreted the lesion as primarily
chronic interstitial pneumonia with a prominent bronchiolocentric
distribution, and noted that extrinsic allergic alveolitis (or
"farmer's lung") in humans is classically characterized
by a histologic triad of bronchiolocentric chronic inflammation,
poorly-formed non-necrotizing granulomas, and areas of organizing
pneumonia. They did not identify the latter two histologic features
in this case, but commented that the bronchiolocentric inflammation
is consistent with hypersensitivity pneumonitis given the correct
clinical setting. In humans, the differential diagnosis for
this lesion would also include infection, collagen vascular disease
and drug reaction.
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- While the clinical history is not available in this case,
the histologic lesions and signalment are compatible with extrinsic
allergic alveolitis as described in cattle. Many participants
considered mycoplasmal bronchitis and bronchiolitis of calves
in the differential diagnosis; however, histologic lesions of
that condition are characterized by suppurative bronchitis and
bronchiolitis with peribronchiolar lymphoid hyperplasia and atelectasis.
The paucity of neutrophils, the presence of globule leukocytes
and eosinophils, and the fibrosis are more consistent with hypersensitivity
pneumonitis.
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- In humans, hypersensitivity pneumonitis includes a variety
of immune-mediated, predominately interstitial lung diseases
caused by intense, prolonged exposure to inhaled organic dusts
and related occupational antigens. Affected individuals have
heightened immune response or abnormal sensitivity to the antigen,
and lesions primarily involve alveoli with progression to chronic
fibrotic lung disease. Sources of antigens vary, and may include
thermophilic bacteria, fungi, animal proteins, and several others.
Experimental and human studies support type III immune complex
reaction for the early lesions, followed by type IV delayed hypersensitivity
reaction for the granulomatous component.
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- Contributor: Department of Pathology, Cornell University,
Ithaca, New York 14853-6401.
-
- References:
- 1. Breeze R: Hypersensitivity pneumonitis. Vet Clin N Am
Food Anim Pract 1:324-330, 1985.
- 2. Grandin T: Euthanasia and slaughter of livestock. J Amer
Vet Med Assoc 204:1354-1360, 1994.
- 3. Kobzik L: The lung. In: Robbins Pathologic Basis of Disease,
Cotran RS, Kumar V, Collins T, eds., 6th ed., pp. 737-738 and
356, WB Saunders, Philadelphia, PA, 1999.
- 4. Jones TC, Hunt RD, King NW: The respiratory system. In:
Veterinary Pathology, Jones TC, Hunt RD, King NW, eds., 6th ed.,
pp. 694-695, Williams & Wilkins, Baltimore, MD, 1997.
- 5. Dungworth DL: The respiratory system. In: Pathology of
Domestic Animals, Jubb KVF, Kennedy PC, Palmer N, eds., 4th ed.,
vol. 2, pp., 575-576, 658-659, 676-677, Academic Press, San Diego,
CA, 1993.
- 6. Van Metre DC: Allergic respiratory disease. Vet Clin
N Amer Food Anim Pract 13:495-512, 1997.
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Case II - CP94-150 (AFIP 2459067)
- Signalment: 15-year-old, male, mixed breed, canine.
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- History: The owner observed pigmented nodules in the
left flank region.
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- Gross Pathology: The skin specimen consisted of a
dark, pigmented, raised nodule measuring 1.8 x 1.5 cm.
Laboratory Results: None.
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- Contributor's Diagnosis and Comments: Nodular cutaneous
amyloidosis.
Etiology: May be directly related to the plasma cell infiltrate.
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- Multiple amyloid deposits are scattered throughout the dermis.
Some deposits are associated with plasma cells, and other deposits
are associated with giant cells. The eosinophilic deposits stained
positive with Congo red and were birefringent (green) when polarized.
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- AFIP Diagnosis: Haired skin: Atypical plasma cell
infiltrate, favor plasmacytoma, with amyloid and granulomatous
inflammation, mixed breed, canine.
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- Conference Note: Most participants agreed with the contributor
and diagnosed cutaneous amyloidosis associated with plasmacytic
and granulomatous inflammation. However, the moderator and a
few participants noted that, aside from the macrophages and multinucleate
giant cells (that appeared to represent a foreign body reaction
to the amyloid), the cellular infiltrate is composed of almost
exclusively plasma cells. Additionally, although most of the
plasma cells are well differentiated, scattered cells are up
to five times the size of normal plasma cells, some plasmacytoid
cells have atypical nuclear features such as nucleoli, and rarely,
plasmacytoid cells contain mitotic figures. These features support
a neoplastic proliferation. Unfortunately, immunohistochemical
stains for light chains did not work properly, and insufficient
material was available for further testing to determine whether
or not the plasma cells are monoclonal. Canine cutaneous plasmacytomas
range from very well differentiated to very poorly differentiated.
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- A recent study of canine extramedullary plasmacytomas confirmed
the previously reported, predominantly benign biological behavior
of these tumors, but noted rare instances of local recurrence
and metastasis by the most pleomorphic subtype. Aside from this
observation, histopathologic grading of plasmacytomas was not
found to be useful.
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- Contributor: St. Jude Children's Research Hospital,
Comparative Medicine/ARC, 332 North Lauderdale, Memphis, TN
38105.
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- References:
- 1. Gross TL, Ihrke PJ, Walder EJ: Dysplastic and depositional
diseases of the dermal connective tissue. In: Veterinary Dermatopathology,
Reinhardt RW, ed., pp. 229-232, Mosby-Yearbook Inc., St. Louis,
MO, 1992.
- 2. Jones TC, Hunt RD, King NW: Intracellular and extracellular
depositions; degenerations. In: Veterinary Pathology, Jones TC,
Hunt RD, King NW, eds., 6th ed., pp. 50-54, Williams & Wilkins,
Baltimore, MD, 1997.
- 3. Rowland RH, et al.: Cutaneous plasmacytomas with amyloid
in six dogs. Vet Pathol 28:125-130, 1991.
- 4. Cotran RS, Kumar V, Collins T: Diseases of immunity.
In: Robbins Pathologic Basis of Disease, Cotran RS, Kumar V,
Collins T, eds., 6th ed., pp. 251-257 and 356, W.B. Saunders,
Philadelphia, PA, 1999.
- 5. Jager JA, Scott DW, Wilcock BP: The skin and appendages.
In: Pathology of Domestic Animals, Jubb KVF, Kennedy PC, Palmer
N, eds., 4th ed., vol. 1, pp. 628, Academic Press, San Diego,
CA, 1993.
- 6. Platz SJ, Breuer W, Pfleghaar S, Minkus G, Hermanns W:
Prognostic value of histopathologic grading in canine extramedullary
plasmacytomas. Vet Pathol 36:23-27, 1999.
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Case III - 60929-C (AFIP 2460487)
- one 2x2 histology color photo transparency
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- Signalment: 4½-year-old, male, German Shepherd
dog.
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- History: The dog came from Fort Walton Beach, Florida.
He had exophthalmia and prolapse of the third eyelid for approximately
1½ months. The referring veterinarian examined the dog
five weeks previously and had treated the dog with KeflexÔ
(500mg, TID) and prednisone (20mg, BID) for seven days. The
exophthalmia improved slightly. The referring veterinarian then
treated the dog with a tapering dose of dexamethasone over the
next 25 days. At the time the dog was examined at Auburn University,
no medications had been administered for one week. According
to the owners, the exophthalmia was less prominent than originally
noted.
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- At Auburn, the dog was depressed, lethargic, and had dark-coated,
soft stool. He had lost 1½ lbs. in the last week. The
temperature was 103.3°F; pulse was 80 beats/minute; and the
respiratory rate was 40 breaths/minute. On physical examination,
the dog had a nasal discharge and appeared to have a nasal mass.
A mass near the left eye was identified in skull radiographs;
however, no tumor was identified by CT. In the process of performing
a rhinoscopic examination and obtaining a nasal biopsy, the dog
went into cardiac and respiratory arrest. Resuscitation was
progressing poorly using external cardiac compression. Upon
opening the thoracic wall to facilitate cardiac massage, 500-800
ml of gray, flocculent fluid spilled out.
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- Gross Pathology: Necropsy was not allowed, but observations
were made during resuscitation attempts. Pericardial fluid was
present, but was not as flocculent as that found in the thoracic
cavity. The pericardium was thickened. There were numerous
pleural adhesions, and several intra-thoracic lymph nodes were
enlarged. Cytologic preparations were made from aspirates of
the nasal mass and the thoracic effusion. Sections for histopathologic
examination were obtained from lung, bronchial lymph nodes, pericardium,
and the nasal mass.
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- Laboratory Results
- Cytologic findings: Nasal and thoracic effusions are
similar. Neutrophils are numerous and often surround or appear
attached to the surface of hyphal elements that are irregularly
branching, variably septate or twisted/compressed, and have thick
nonparallel walls often with bulbous ends or sections. There
is abundant gray-blue, amorphous proteinaceous material in the
background.
Cytologic opinion: Purulent inflammation with numerous
mycotic organisms; evidence of necrosis.
Mycotic culture performed at Auburn University resulted in growth
of Conidiobolus sp. (probably not C. coronatus). Mycotic culture
performed at the Fungus Testing Laboratory in San Antonio, Texas
resulted in the growth of Conidiobolus (not consistent with C.
coronatus).
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- Contributor's Diagnosis and Comments: Lymph node:
Pyogranulomatous, necrotizing, mycotic lymphadenitis.
Etiologic agent: Conidiobolus sp.
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- The architecture of this bronchial lymph node is effaced
focally to locally extensively. Multifocal areas have increased
numbers of large epithelioid macrophages, often in sheets. Other
areas have necrotic centers with neutrophils, cellular debris,
and scattered negative reliefs of oval to irregular structures
that are sometimes surrounded by intensely acidophilic amorphous
material. Macrophages, fewer neutrophils, and scattered multinucleated
giant cells are adjacent to the necrotic centers. Plasma cells
are increased in lymphoid follicular structures nearest the granulomas
and necrotic areas. The submitted photomicrograph of a Grocott's
methenamine silver (GMS) stained section demonstrates many thin-walled,
irregularly shaped, broad hyphae within and adjacent to areas
of necrosis.
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- In other tissues (not submitted), the left nasal cavity has
abundant purulonecrotic material on the surfaces with numerous
fungal hyphae. The pericardium has mild, diffuse infiltration
of neutrophils and several wide, septate hyphae on the surface.
The lung tissue has thickened pleura and an infiltration of
macrophages and fewer neutrophils. Wide, septate hyphae are
on the surface.
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- Conidiobolus sp. are classified as follows (according to
Goodman and Rinaldi):
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- Superkingdom: Eukaryotae
Kingdom: Fungi
Division: Zygomycotina
Class: Zygomycetes
Order: Entomophthorales
Family: Ancylistaceae
- Genus: Conidiobolus
- Subgenus: Conidiobolus
- Pathogenic species:
- 1. Conidiobolus coronatus
- 2. Conidiobolus incongruus
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- Conidiobolus coronatus infections are typically limited to
the nasal cavity with occasional extension into the cerebrum
(rhinocerebral infections) and have been diagnosed most often
in horses from tropical and semitropical areas (Chandler, Bridges)
and in one llama (French). Conidiobolus incongruus infections
have been reported in sheep in Australia (Ketterer, Carrigan)
and have had nasal, pulmonary, and thoracic cavity involvement.
A case of disseminated Conidiobolus infection (species not compatible
with any known variant) has been reported in a man who was a
crack cocaine addict (Jaffey). This dog was suspected to be
immunosuppressed owing to the prolonged administration of corticosteroids.
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- AFIP Diagnosis: Lymph node and perinodal adipose tissue:
Lymphadenitis, granulomatous and eosinophilic, necrotizing, multifocal
and coalescing, moderate, with perinodal steatitis, lymphangitis
and fungal hyphae surrounded by radiating eosinophilic hyaline
material (Splendore-Hoeppli material), German Shepherd Dog, canine.
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- Conference Note: In some sections, sinus histiocytosis,
hemosiderosis, and erythrophagocytosis are present. Participants
noted a paucity of lymphoid follicles, but the presence of many
plasma cells. Significant numbers of eosinophils are associated
with fungal hyphae. Several participants observed anisotropic
crystals within macrophages (silicosis), suggesting that the
lymph node drained the respiratory tract.
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- Zygomycosis is a disease of humans and animals caused by
fungi belonging to the class Zygomycetes. The pathogenic Zygomycetes
include members of two orders that are histomorphologically similar
but cause differing types of disease: Mucorales and Entomophthorales.
The Mucorales cause mucormycosis and include the genera Rhizopus,
Mucor, Rhizomucor, Mortierella, Absidia, and others. The Entomophthorales
include Basidiobolus and Conidiobolus sp., and disease induced
by these fungi is termed entomophthoromycosis.
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- Generally, the Mucorales cause invasive, disseminated disease
in humans and animals. Mucormycosis commonly occurs in debilitated
hosts, and systemic zygomycosis is usually caused by the Mucorales.
Rhinocerebral zygomycosis is a fulminating, often fatal disease
in humans which most commonly occurs in individuals suffering
from acute diabetes mellitus or other immunosuppressive conditions.
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- The Entomophthorales tend to cause localized subcutaneous
and nasal granulomas in humans and animals. In humans, for example,
infections with Conidiobolus coronatus are limited to the nasal
mucosa and sinuses, and the subcutaneous tissue of the nose and
face. With few exceptions, zygomycosis caused by Basidiobolus
and Conidiobolus occurs in healthy individuals and does not disseminate.
Exceptions to these generalities include rhinocerebral and disseminated
infections of sheep in Australia caused by Conidiobolus incongruus,
and a few reports of invasive and disseminated infections in
humans caused by C. incongruus and other Conidiobolus sp.
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- In addition to variation in clinicopathologic presentation
between infection with the Mucorales and Entomophthorales, differences
in histologic lesions have also been observed. The presence
of Splendore-Hoeppli material and eosinophilic inflammation is
more consistent with infection by the Entomophthorales. The
Mucorales tend to invade vessels, causing necrotizing vasculitis,
thrombosis, and infarction while the Entomophthorales do not
typically cause vascular lesions.
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- Differential diagnosis for zygomycosis includes Pythium insidiosum
and Aspergillus sp. The fungal hyphae of the Zygomycetes are
broad (3-25 mm, avg. 12), thin-walled, infrequently septate,
have nonparallel sides, and measure up to 200 mm in length.
They are characterized by nondichotomous, irregular branching
that sometimes occurs at right angles. Frequently, the hyphae
of Mucorales are easily observed in standard hematoxylin and
eosin stained sections. The hyphae of Entomophthorales are often
surrounded by Splendore-Hoeppli material. The hyphae of the
protist Pythium of the phylum Oomycetes, are narrower (2 to 6
mm), have thicker walls, and are found most often at the periphery
of necrotic areas. In general, the hyphae of Aspergillus are
3 to 6 mm, have dichotomous branching, parallel walls, numerous
septa, and may be difficult to observe in standard H & E
stained tissue sections. Special stains, such as the periodic
acid-Schiff reaction and the Gomori's methenamine silver method,
frequently stain the hyphae of Aspergillus more intensely than
the Zygomycetes.
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- Contributor: Auburn University, Department of Pathobiology,
College of Veterinary Medicine, Auburn University, AL 36849-5519.
-
- References:
- 1. Goodman NL, Rinaldi MG: Agents of zygomycosis. In: Manual
of Clinical Microbiology, Balows A, et al., eds., 5th edition,
pp. 674-690, American Society for Microbiology, Washington, 1991.
- 2. Bridges CH, Romane WM, Emmons CW: Phycomycosis of horses
caused by Entomophthora coronatus. J Amer Vet Med Assoc 140:673-677,
1962.
- 3. Chandler FW, Kaplan W, Ajello L: In: Color Atlas and
Text of the Histopathology of Mycotic Diseases, Chandler FW,
Kaplan W, Ajello L, eds., pp. 122-127, Year Book Medical Publishers,
Chicago, 1980.
- 4. Carrigan MJ, Small AC, Perry GH: Ovine nasal zygomycosis
caused by Conidiobolus incongruus. Aust Vet J 69:237-240, 1992.
- 5. French RA, Ashworth CD: Zygomycosis caused by Conidiobolus
coronatus in a llama (Llama glama). Vet Pathol 31:120-122, 1994.
- 6. Jaffey PB, Haque AK, El-Zaatari M, Pasarell L, McGinnis
MR: Disseminated Conidiobolus infection with endocarditis in
a cocaine abuser. Arch Pathol Lab Med 114:1276-1278, 1990.
- 7. Ketterer PJ, et al.: Rhinocerebral and nasal zygomycosis
in sheep caused by Conidiobolus incongruus. Aust Vet J 69:85-87,
1992.
- 8. Jager JA, Scott DW, Wilcock BP: The skin and appendages.
In: Pathology of Domestic Animals, Jubb KVF, Kennedy PC, Palmer
N, eds., 4th ed., vol. 1, pp. 670-672, Academic Press, San Diego,
CA, 1993.
- 9. Jones TC, Hunt RD, King NW: Diseases caused by fungi.
In: Veterinary Pathology, Jones TC, Hunt RD, King NW, eds., 6th
ed., pp. 523-525, Williams & Wilkins, Baltimore, MD, 1997.
- 10. Foil CS: Miscellaneous fungal diseases. In: Infectious
Diseases of the Dog and Cat, Greene CE, ed., 2nd ed., pp. 423-425,
W.B. Saunders, Philadelphia, PA, 1998.
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Case IV - A41168 (AFIP 2638283)
- Signalment: Five-year-old, male, Belgian Malinois,
dog.
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- History: The dog had a history of seizures and had
been treated with barbiturates for more than a year. Recently,
the dog also had a history of anorexia, vomiting, and weight
loss. The dog developed ulcerative hyperkeratotic lesions on
all four feet.
-
- Gross Pathology: There was bilateral ulceration on
the skin of the elbows. All four feet had ulcerative skin of
dorsal terminal digits and hyperkeratosis on the paws. The liver
was nodular, smaller than normal in size, and had a thick, opaque,
fibrotic capsule.
-
- Laboratory Results:
- Blood chemistry tests revealed alkaline phosphatase was increased
(1823 IU/L); SGPT (ALT) was increased (101); CPK was increased
(656 IU/L); BUN was decreased (6 mg/L); and total bilirubin was
increased (0.5 mg/L).
- Urinalysis results were bilirubin 3+; blood 3+; protein 3+.
-
- Contributor's Diagnosis and Comments: Superficial
necrolytic dermatitis (hepatocutaneous syndrome).
-
- Morphologically, the skin had marked parakeratosis and necrosis
in the stratum corneum, vacuolization of the epithelium in the
stratum spinosum, epidermal necrosis with occasional presence
of bacterial colonies, and infiltration of neutrophils. These
lesions are typical of superficial necrolytic dermatitis (hepatocutaneous
syndrome). The dog also had severe hepatic cirrhosis. The lesions
are similar to those in the pig or dog with zinc deficiency.
-
- AFIP Diagnosis: Footpad and adjacent haired skin:
Parakeratosis, diffuse, severe, with moderate epidermal hyperplasia,
multifocal superficial epidermal pallor, mild lymphoplasmacytic
and histiocytic superficial dermatitis, dermal edema, and intracorneal
colonies of cocci, Belgian Malinois, canine.
-
- Note: Some sections contain folliculitis, furunculosis,
and intracorneal and subcorneal pustules.
- Conference Note: Superficial necrolytic dermatitis (SND)
is an uncommon skin disease of dogs with similarities to necrolytic
migratory erythema (NME) in humans. The human disease is primarily
a paraneoplastic syndrome associated with pancreatic endocrine
tumors that secrete glucagon (glucagonoma) resulting in high
blood levels of glucagon. Although a minority of canine cases
have been associated with glucagon producing pancreatic endocrine
tumors, the condition most often has been associated with chronic
hepatic disease and diabetes mellitus, thus the term hepatocutaneous
syndrome. The disease in the dog is primarily a manifestation
of internal metabolic derangement rather than a manifestation
of a specific diagnostic entity as in humans. The disease is
primarily seen in older dogs, and seems to occur more frequently
in females.
Gross lesions are usually bilateral, and the affected skin is
erythematous, eroded, ulcerated, and crusted. Lesions occur
on the footpads, mucocutaneous junctions, edges of the pinnae,
pressure points on the distal extremities, ventral thorax, and
scrotum. Microscopically, diagnostic features include the presence
of pale staining keratinocytes in the superficial half of an
acanthotic stratum spinosum (white), located between the parakeratotic,
crusted stratum corneum (red) and the hyperplastic basal cell
layer and deeper stratum spinosum (blue). Pallor of the upper
stratum spinosum may not be present in all sections. Clefts
and vesicles may form in the outer stratum spinosum as cells
degenerate, and subcorneal pustules may be present. Secondary
bacterial and fungal infections may occur.
-
- The pathogenesis of SND in dogs and NME in humans is not
completely understood, but hypoaminoacidemia caused by metabolic
disease or hormonal abnormalities may be the common underlying
etiology in both conditions. High glucagon levels in functional
glucagonomas in humans are known to induce hypoaminoacidemia
through prolonged gluconeogenesis, depleting the serum and skin
of essential amino acids and leading to degeneration and necrosis
of keratinocytes. In dogs, chronic hepatic and metabolic diseases
may have a similar result. Indeed, dermatoses associated with
poor quality diets (generic dog food dermatosis) and zinc-responsive
dermatoses have similar histologic features and probably have
a similar pathogenesis.
-
- In addition to zinc deficiency and generic dog food dermatosis,
other parakeratotic hyperplastic dermatitides which might be
considered in the differential diagnosis include lethal acrodermatitis
of Bull terriers and thallium toxicosis. The clinical differential
diagnosis might also include erythema multiforme, toxic epidermal
necrolysis, systemic lupus erythematosus, and pemphigus foliaceus.
-
- Contributor: Department of Pathology, The Animal Medical
Center, 510 East 62nd Street, New York, NY 10021.
-
- References:
- 1. Miller WH, et al.: Necrolytic migratory erythema in dogs:
A hepatocutaneous syndrome. J Amer Anim Hosp Assoc 26:573-581,
1990.
- 2. Kasper CS, McMurry K: Necrolytic migratory erythema without
glucagonoma versus canine superficial necrolytic dermatitis:
Is hepatic impairment a clue to pathogenesis? J Amer Acad Dermatol
25:534-541, 1991.
- 3. Kernkamp HCH, Ferrin EF: Parakeratosis in swine. J Amer
Vet Med Assoc 123:217-220, 1953.
- 4. Robertson BT, Burns MJ: Zinc metabolism in zinc-deficiency
syndrome in the dog. Amer J Vet Res 24:997-1002, 1963.
- 5. Gross TL, Ihrke PJ, Walder EJ: Diseases of the epidermis
In: Veterinary Dermatopathology, Reinhardt RW, ed., pp. 46-48,
102-105, Mosby-Yearbook Inc., St. Louis, MO, 1992.
- 6. Gross TL, Song MD, Havel PJ, Irhke PJ: Superficial necrolytic
dermatitis (necrolytic migratory erythema) in dogs. Vet Pathol
30:75-81, 1993.
- 7. Munson L, Koehler JW, Wilkinson JE, Miller RE: Vesicular
and ulcerative dermatopathy resembling superficial necrolytic
dermatitis in captive black rhinoceroses (Diceros bicornis).
Vet Pathol 35:31-42, 1998.
- 8. Lewis DT: Life-threatening dermatoses. Comp Contin Med
Ed Small Anim Pract 20:271-282, 1998.
-
- Wednesday Slide Conference Coordinator:
-
- Ed Stevens, DVM
Captain, United States Army
Registry of Veterinary Pathology*
Department of Veterinary Pathology
Armed Forces Institute of Pathology
(202)782-2615; DSN: 662-2615
Internet: STEVENSE@afip.osd.mil
-
- * The American Veterinary Medical Association and the American
College of Veterinary Pathologists are co-sponsors of the Registry
of Veterinary Pathology. The C.L. Davis Foundation also provides
substantial support for the Registry.
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