Ophthalmic, Reproductive, Hematologic/Lymphatic, and Oncologic Diseases – BCSE Study Guide

Overview and Clinical Importance

This comprehensive guide covers four critical body system categories within the Medicine domain: ophthalmic diseases, reproductive diseases, hematologic and lymphatic diseases, and oncologic diseases. Together, these topics represent a significant portion of the BCSE examination and require understanding of both pathophysiology and clinical management across multiple species.

Section 1: Ophthalmic Diseases

Corneal Ulcers

Corneal ulcers are breaks in the corneal epithelium that can progress to involve deeper layers. They are among the most common ophthalmic emergencies in veterinary practice and require prompt diagnosis and treatment to prevent vision loss.

[Include Image: Figure 1. Fluorescein staining of corneal ulcer showing bright green uptake in affected area]

Classification by Depth

MEMORY TIP - ULCER Depth Mnemonic: "Some Surgeons Demand Perfection" - Superficial, Stromal, Descemetocele, Perforated (in order of increasing severity)

Indolent (SCCED) Ulcers

Spontaneous Chronic Corneal Epithelial Defects (SCCEDs) are superficial ulcers that fail to heal within 1-2 weeks despite appropriate treatment. They have characteristic loose, non-adherent epithelial edges. Most common in middle-aged to older dogs, with Boxers predisposed.

MEMORY TIP - BOXER Rule: When you see an older dog with a non-healing superficial ulcer with loose epithelial edges, think BOXER and SCCED. Treatment requires debridement plus grid keratotomy (NOT in cats - causes sequestrum!)

Treatment Approach

• Simple superficial ulcers: Topical broad-spectrum antibiotics (e.g., neomycin-polymyxin-bacitracin), E-collar, recheck in 5-7 days
• Stromal/deep ulcers: Aggressive topical antibiotics (fluoroquinolones), serum/plasma for anticollagenase activity, mydriatic (atropine 1%), oral pain management
• Melting ulcers: EMERGENCY - requires hourly topical treatment initially, consider serum, systemic doxycycline (anticollagenase), referral for surgery

Glaucoma

Glaucoma is elevated intraocular pressure (IOP) causing damage to the optic nerve and retina. Normal IOP in dogs and cats is 15-25 mmHg. Acute glaucoma is an EMERGENCY - vision can be lost within 24-48 hours.

[Include Image: Figure 2. Acute glaucoma showing buphthalmos, episcleral congestion, and mydriatic pupil]

MEMORY TIP - Primary Glaucoma Breeds - "CBCSS + BH": Cocker, Basset, Chow, Shar Pei, Siberian (Husky), Beagle, Boston Husky - these breeds need prophylactic treatment in the unaffected eye!

Clinical Signs

• Acute: Pain, blepharospasm, episcleral congestion, corneal edema, mydriatic (dilated) fixed pupil, vision loss
• Chronic: Buphthalmos (enlarged globe), lens luxation/subluxation, optic nerve cupping, blindness

Emergency Treatment

• Topical prostaglandin analogs (latanoprost) - increases uveoscleral outflow. CONTRAINDICATED in uveitis or lens luxation!
• Carbonic anhydrase inhibitors (dorzolamide, brinzolamide) - decrease aqueous production
• Osmotic diuretics (IV mannitol 1-2 g/kg over 20 min) for rapid IOP reduction
• Goal: IOP less than 20 mmHg within 24 hours

MEMORY TIP - Latanoprost Contraindications - "LUL": Lens Luxation, Uveitis, Luxation - do NOT use prostaglandin analogs in these conditions as they worsen inflammation/lens movement

Keratoconjunctivitis Sicca (KCS/Dry Eye)

KCS results from inadequate tear production leading to corneal and conjunctival inflammation. Most common cause in dogs is immune-mediated destruction of lacrimal glands. Normal Schirmer Tear Test (STT) value is greater than 15 mm/min.

MEMORY TIP - STT Interpretation: "15 is FINE" - Greater than 15 mm/min is normal. Think of tears taking 15 seconds to fill a cup!

Clinical Signs and Breeds

Clinical Signs: Mucopurulent discharge (thick, stringy), conjunctival hyperemia, corneal vascularization, pigmentation, ulceration, dull lackluster cornea. Predisposed breeds: English Bulldog, Cocker Spaniel, West Highland White Terrier, Lhasa Apso, Shih Tzu, Yorkshire Terrier.

MEMORY TIP - KCS Breed Predisposition - "COWBOY WEST": Cocker, One-eyed breeds (brachycephalics), West Highland White, Bulldog (English), Yorkshire (Terrier) - breeds prone to dry eye

Treatment

• Lacrimostimulants: Cyclosporine 0.2% or tacrolimus 0.02-0.03% - restore tear production, anti-inflammatory, requires 4-8 weeks for effect
• Artificial tears: Use frequently (every 2-4 hours initially) as adjunct
• Topical antibiotics: For secondary bacterial infection
• Surgery: Parotid duct transposition for refractory cases (redirects saliva to eye)

Cataracts

A cataract is any opacity of the lens. Cataracts are classified by stage (incipient, immature, mature, hypermature), location (nuclear, cortical, capsular), and cause (hereditary, diabetic, senile, traumatic, secondary to uveitis).

MEMORY TIP - Cataract Stages - "I May Mention Hypermature": Incipient (less than 10-15% opacity), Immature (incomplete opacity, tapetum visible), Mature (complete opacity, no tapetum reflection), Hypermature (wrinkling, resorption)

Uveitis

Uveitis is inflammation of the uveal tract (iris, ciliary body, choroid). Can be anterior (iridocyclitis), posterior (choroiditis), or panuveitis. Always look for underlying cause.

MEMORY TIP - Uveitis vs Glaucoma - "PAIN Opposites": Uveitis = Pain, Aqueous flare, IOP LOW, Narrow pupil (miosis). Glaucoma = Pain, Aqueous clear, IOP HIGH, Wide pupil (mydriasis)

Section 2: Reproductive Diseases

Pyometra

Pyometra is accumulation of purulent material within the uterus, typically occurring during diestrus (luteal phase) in intact females. It is a potentially life-threatening condition requiring prompt diagnosis and treatment. Most common pathogen is Escherichia coli.

[Include Image: Figure 3. Ultrasonographic image of pyometra showing enlarged fluid-filled uterine horns]

MEMORY TIP - Pyometra Timing - "6-6-6 Rule": Typically occurs 6-10 weeks after estrus, within 6 months of last heat, most common in dogs over 6 years old. Think of 6 as the magic number!

Clinical Signs

• Polyuria/polydipsia (PU/PD) - most common owner complaint
• Vulvar discharge (open) - purulent, serosanguinous, or mucopurulent
• Lethargy, anorexia, vomiting, dehydration
• Fever or hypothermia (sepsis)
• Abdominal distension/palpable uterus

Diagnosis and Treatment

Diagnostics: CBC (leukocytosis with left shift, or leukopenia in severe cases), biochemistry (azotemia common), abdominal radiographs/ultrasound (enlarged tubular uterus). Treatment of choice: Ovariohysterectomy (OVH) after stabilization with IV fluids and broad-spectrum antibiotics. Medical management with prostaglandins (dinoprost) and/or aglepristone (progesterone receptor antagonist) may be considered for breeding animals but has lower success rate and risk of recurrence.

MEMORY TIP - Pyometra Lab Changes: "WBC goes UP, URINE gets watery" - leukocytosis common, plus isosthenuria (SG 1.008-1.012) due to E. coli endotoxin effect on kidneys

Metritis

Acute postpartum metritis is a life-threatening bacterial infection of the uterus occurring within 1-3 weeks after parturition. Unlike pyometra, the cervix is typically open. Common causes include retained placenta, dystocia, and obstetric manipulation.

MEMORY TIP - Metritis vs Pyometra Timing: "M comes after birth (Mom just delivered), P comes after heat" - Metritis = postpartum, Pyometra = post-estrus during diestrus

Dystocia

Dystocia is difficult or abnormal labor. Can result from maternal factors (uterine inertia, pelvic abnormalities) or fetal factors (malposition, oversized fetus, fetal death). Early recognition and intervention are critical for maternal and fetal survival.

Indications for Intervention

• Stage I labor greater than 24 hours (dogs) or 36 hours (cats)
• Stage II labor greater than 4 hours without producing a puppy/kitten
• Greater than 2 hours between neonates
• Active straining for greater than 30 minutes without delivery
• Green/black discharge before first neonate (indicates placental separation)
• Signs of systemic illness, pain, or exhaustion

MEMORY TIP - Dystocia Intervention Rules - "4-2-30": Greater than 4 hours without first pup, greater than 2 hours between pups, greater than 30 minutes of active straining = TIME TO INTERVENE

Management

• Medical: Oxytocin (0.5-2 IU IM, may repeat every 30 min x 2-3 doses) - ONLY if cervix dilated and no obstruction
• Calcium gluconate 10% (1-5 mL slow IV) - for uterine inertia secondary to hypocalcemia
• Surgical: Cesarean section for obstructive dystocia, failed medical management, or maternal/fetal distress

Cryptorchidism

Cryptorchidism is failure of one (unilateral) or both (bilateral) testes to descend into the scrotum. The retained testis may be inguinal or abdominal. It is hereditary and affected animals should not be bred.

MEMORY TIP - Cryptorchid Cancer Risk - "TEN Times Trouble": Retained testes have 10x increased risk of becoming cancerous. Sertoli cell tumors in retained testes can cause feminization syndrome.

Section 3: Hematologic and Lymphatic Diseases

Immune-Mediated Hemolytic Anemia (IMHA)

IMHA is destruction of red blood cells by the immune system. It is one of the most common immune-mediated diseases in dogs and carries significant morbidity and mortality (30-40% mortality rate). Can be primary (idiopathic/autoimmune) or secondary (triggered by drugs, infections, neoplasia).

[Include Image: Figure 4. Blood smear showing spherocytes and polychromasia in IMHA]

Diagnostic Criteria (ACVIM Consensus)

• Anemia (PCV less than 35%)
• Evidence of hemolysis: Hyperbilirubinemia, bilirubinuria, hemoglobinuria, hemoglobinemia
• Evidence of immune-mediated destruction (at least ONE): Spherocytosis, positive saline agglutination test, positive Coombs test (DAT)

MEMORY TIP - IMHA Triad - "SAC": Spherocytes, Agglutination, Coombs positive - these are the three hallmarks of immune-mediated RBC destruction

Saline Agglutination Test

Mix 1 drop of EDTA blood with 4 drops of saline on a slide. True agglutination (clumps of RBCs that do NOT disperse with saline) indicates IMHA. Rouleaux (stacked coins) WILL disperse with saline dilution - this is NOT agglutination.

MEMORY TIP - Rouleaux vs Agglutination: "Rouleaux Runs away with saline, Agglutination Acts stubborn" - Rouleaux disperses with saline, true agglutination persists

Treatment Protocol

Immune-Mediated Thrombocytopenia (ITP)

ITP is immune-mediated destruction of platelets causing thrombocytopenia. Can occur alone or concurrently with IMHA (Evans syndrome). Diagnosed by exclusion - rule out other causes of thrombocytopenia.

Clinical Signs

• Petechiae (pinpoint hemorrhages) - especially on mucous membranes, pinnae, ventral abdomen
• Ecchymoses (bruising)
• Melena, hematuria, epistaxis
• Often presents with platelet count less than 20,000-30,000/microliter

MEMORY TIP - Platelet Bleeding Pattern: "Platelets make Petechiae" - Primary hemostatic defects (platelet problems) cause petechiae, ecchymoses, mucosal bleeding. Secondary hemostatic defects (coagulation factor problems) cause hematomas, joint bleeding, body cavity hemorrhage.

Diagnostic Workup

Always rule out other causes of thrombocytopenia: Infectious (tick-borne diseases - Ehrlichia, Anaplasma), DIC, drug-induced, neoplasia, bone marrow disease. Check PT/PTT to rule out concurrent coagulopathy. Bone marrow aspirate may show megakaryocytic hyperplasia (increased platelet production in response to destruction).

Evans Syndrome

Evans syndrome is the concurrent presence of IMHA and ITP. These patients are often more severely affected and have a worse prognosis than those with either condition alone. Treatment combines approaches for both conditions.

MEMORY TIP - Evans Syndrome = "E" for "Everything" attacked: The immune system attacks BOTH red blood cells AND platelets - double trouble!

Von Willebrand Disease (vWD)

vWD is the most common inherited bleeding disorder in dogs. Von Willebrand factor (vWF) is needed for platelet adhesion to damaged endothelium. Deficiency causes prolonged bleeding, especially from mucosal surfaces.

MEMORY TIP - vWD Type 1 Breeds - "Dogs Get Severely Sick": Doberman, German Shepherd, (Standard) Poodle, Shetland Sheepdog - these breeds have Type 1 vWD

Diagnosis and Management

• Buccal mucosal bleeding time (BMBT) - prolonged in vWD
• vWF antigen assay - definitive test (less than 50% is suggestive, less than 35% often clinical)
• PT/PTT usually normal (primary hemostasis issue, not coagulation cascade)
• Treatment: Cryoprecipitate or fresh frozen plasma for bleeding. Desmopressin (DDAVP) transiently increases vWF release in Type 1.

Section 4: Oncologic Diseases

Lymphoma

Lymphoma is one of the most common cancers in dogs and cats. In dogs, multicentric lymphoma (peripheral lymphadenopathy) is most common. In cats, alimentary (GI) lymphoma is most common, followed by mediastinal and multicentric forms. FeLV association is decreasing due to vaccination.

[Include Image: Figure 5. Dog with multicentric lymphoma showing generalized peripheral lymphadenopathy]

WHO Clinical Staging

Substages: a = no systemic signs, b = systemic signs present (anorexia, weight loss, lethargy)

MEMORY TIP - Lymphoma Staging - "1 Node, 2 Regional, 3 Generalized, 4 Liver/Spleen, 5 Blood/Bone Marrow": Think of it spreading further from 1 to 5. Stage III is when it crosses the diaphragm (3 looks like diaphragm dividing body).

Immunophenotype and Prognosis

MEMORY TIP - B-cell vs T-cell Prognosis: "B is Better, T is Terrible" - B-cell lymphoma has better prognosis. T-cell is associated with hypercalcemia (humoral hypercalcemia of malignancy).

Treatment - CHOP Protocol

The CHOP protocol is the standard of care for canine lymphoma. C = Cyclophosphamide, H = Hydroxydaunorubicin (Doxorubicin), O = Oncovin (Vincristine), P = Prednisone. Multi-agent protocols achieve better outcomes than single-agent.

MEMORY TIP - CHOP Protocol Drugs: "CHOP down lymphoma" - Cyclophosphamide (alkylating agent), H-doxorubicin (anthracycline - watch for cardiotoxicity!), Oncovin/Vincristine (vinca alkaloid - causes peripheral neuropathy), Prednisone (corticosteroid)

Mast Cell Tumors (MCT)

Mast cell tumors are the most common cutaneous neoplasm in dogs (16-21% of skin tumors). Behavior is highly variable - from benign to highly malignant. They release histamine and other vasoactive substances causing local inflammation and systemic effects.

[Include Image: Figure 6. Cytology of mast cell tumor showing cells with abundant purple metachromatic granules]

Grading Systems

MEMORY TIP - Kiupel High-Grade Criteria - "7 MBK": Greater than 7 mitoses, Multinucleated cells, Bizarre nuclei, Karyomegaly - any ONE of these makes it HIGH grade

Clinical Features and Treatment

• Darier sign: Manipulation causes degranulation leading to erythema, edema, wheal formation
• GI ulceration: Histamine stimulates H2 receptors causing increased gastric acid
• Surgery: Wide excision (2-3 cm margins, one fascial plane deep) is treatment of choice
• Adjunct: H1 and H2 blockers (diphenhydramine + famotidine) perioperatively
• Chemotherapy: Vinblastine + prednisone for high-grade or metastatic. Tyrosine kinase inhibitors (toceranib, masitinib) for c-KIT mutated tumors.

MEMORY TIP - MCT Perioperative Protocol - "Double H Block": H1 blocker (diphenhydramine) + H2 blocker (famotidine) before surgery to prevent histamine release complications

Hemangiosarcoma (HSA)

Hemangiosarcoma is a highly malignant tumor of vascular endothelium. Most commonly affects the spleen, right atrium, and liver. Has an extremely high metastatic rate (greater than 90%). German Shepherds, Golden Retrievers, and Labrador Retrievers are predisposed.

[Include Image: Figure 7. Intraoperative view of ruptured splenic hemangiosarcoma with hemoabdomen]

Common Presentations

MEMORY TIP - HSA Presentation - "Triple G Breeds Get HSA": German Shepherd, Golden Retriever - breeds at highest risk. Think of them Galloping to the emergency room with acute collapse.

Diagnosis and Staging

• Emergency stabilization first: IV fluids, blood products for acute hemorrhage
• Abdominal ultrasound: Splenic mass with peritoneal effusion
• Echocardiography: Rule out cardiac involvement and pericardial effusion
• Thoracic radiographs: Screen for pulmonary metastases (though micro-mets often present)
• DO NOT aspirate splenic masses - risk of hemorrhage and seeding

MEMORY TIP - Splenic Mass Rule of "Halves": In dogs with splenic masses: Half are malignant (HSA is the most common). Of the malignant ones, half have ruptured. Of those that rupture, half die acutely.

Mammary Tumors

Mammary tumors are the most common tumor in intact female dogs. Approximately 50% are malignant in dogs and 85-90% are malignant in cats. Early spaying dramatically reduces risk.

MEMORY TIP - Mammary Protection - "Before 1, Risk is None": Spaying before first heat cycle gives nearly complete protection. Risk increases with each subsequent cycle.

Prognostic Factors

• Size: Tumors less than 3 cm have better prognosis than tumors greater than 3 cm
• Histologic type: Carcinomas worse than adenomas. Inflammatory carcinoma is worst.
• Lymph node involvement: Metastasis indicates worse prognosis
• Surgical margins: Complete excision is critical

Treatment

Surgery is the treatment of choice. In dogs, regional mastectomy (removal of affected gland and associated glands sharing lymphatic drainage) is recommended. In cats, radical (unilateral or bilateral) mastectomy is recommended due to high malignancy rate. Always stage with thoracic radiographs and abdominal ultrasound before surgery. Concurrent OVH does not improve survival but prevents hormone influence on any residual disease.

Osteosarcoma (OSA)

Osteosarcoma is the most common primary bone tumor in dogs (85% of bone tumors). Highly aggressive and metastatic. Typically affects appendicular skeleton of large/giant breed dogs. Median age 7-8 years.

Common Locations

MEMORY TIP - OSA Location - "Away from the Elbow, Toward the Knee": Metaphysis of long bones. Distal radius/ulna, proximal humerus (away from elbow). Distal femur, proximal tibia (toward knee). "APDT" = Away Proximal (humerus), Distal Towards knee

Radiographic Appearance

Classic appearance is aggressive bone lesion in metaphysis with "sunburst" periosteal reaction, lysis, and soft tissue swelling. Codman triangle (lifting of periosteum) may be present. Must differentiate from fungal osteomyelitis in endemic areas.

[Include Image: Figure 8. Radiograph showing classic osteosarcoma appearance with aggressive lytic lesion and sunburst periosteal reaction]

Treatment and Prognosis

MEMORY TIP - OSA Prognosis Numbers: "4-12 Rule" - Amputation alone = 4 months. Amputation + chemo = 12 months (approximately). Chemotherapy approximately TRIPLES survival!

Ophthalmic Diseases

• Acute glaucoma is an EMERGENCY - high IOP, dilated fixed pupil, episcleral congestion; treat with prostaglandin analogs + carbonic anhydrase inhibitors
• KCS diagnosis: Schirmer Tear Test less than 15 mm/min; treat with cyclosporine (lifelong)
• Descemetocele = surgical emergency; appears as clear donut with stained edges
• Grid keratotomy for indolent ulcers in DOGS only (contraindicated in cats)

Reproductive Diseases

• Pyometra occurs 6-10 weeks post-estrus; PU/PD is classic due to E. coli endotoxin; OVH is treatment of choice
• Metritis occurs within 1-3 weeks postpartum; associated with dystocia/retained placenta
• Dystocia intervention: greater than 4 hours without first neonate, greater than 2 hours between neonates, greater than 30 minutes active straining
• Cryptorchid testes have 10x increased cancer risk - always remove both testes

Hematologic Diseases

• IMHA triad: Spherocytes, Agglutination (saline test), Coombs positive
• Thromboprophylaxis is CRITICAL in IMHA - thromboembolism is major cause of death
• ITP presents with petechiae/ecchymoses - always rule out tick-borne diseases first
• vWD: Normal platelet count, normal PT/PTT, prolonged BMBT

Oncologic Diseases

• Lymphoma: B-cell has better prognosis than T-cell; CHOP protocol is standard treatment
• MCT: 2-tier Kiupel grading preferred; use H1 + H2 blockers perioperatively
• HSA: Highly metastatic (greater than 90%); surgery alone = 1-2 months MST, + chemo = 6 months
• OSA: Amputation alone = 4 months, + chemo = 12 months MST; metastases present at diagnosis in 90%
• Mammary tumors: 50% malignant in dogs, 90% malignant in cats; spaying before first heat nearly eliminates risk