HEMOPOIETIC RESPONSES OF THE CAT TO TOTAL BODY IRRADIATION FOLLOWED BY CHEMOTHERAPY

Cats with lymphosarcoma are affected with rapidly progressive, fatal neoplasia of hemopoietic tissues. The very aggressive nature of this type of neoplasia requires intense therapy, which in most instances is only palliative. A combination of total body irradiation and cytotoxic chemotherapy in four normal cats was followed by similar patterns of leukopenia and throm-bocytopenia in all cats. The radiation protocol and the complications of the transient throm-bocytopenia and leukopenia are discussed and compared with reports of similar efforts in human medicine. The responses from these normal cats were quite similar to those seen in humans undergoing similar therapy. The cat may be considered as a possible model for further radiotherapy research.     

Bronchogenic adenocarcinoma in a cat: an unusual case of metastasis to the skin

A 6-year-old, spayed, female, domestic shorthair cat was presented for decreased activity. A nodular lesion was found in the skin extending into the subcutaneous tissue of the right abdominal flank. On lateral and ventrodorsal radiographs of the thorax, an opacity involving the entire right caudal lung lobe and pleural effusion were noted. Cytologic evaluation of cells in the thoracic fluid and in the mass revealed a population of atypical epipthelial cells with marked anisocytosis and high N:C ratios, organized in acinar-like clusters. Multinucleated cells and several mitotic figures were found. The cytologic interpretation was carcinoma. Because of the progressive severity of clinical signs, the cat was euthanized. Histologic evaluation of tissues obtained at necropsy indicated a bronchogenic adenocarcinoma in the lung, with metastasis to the skin of the right flank, but no involvement of the digits. Based on immunohistochemical stains, the neoplastic cells strongly co-expressed cytokeratin and vimentin, and were negative for S-100 and actin-specific antigen. Bronchogenic adenocarcinoma is an uncommon neoplasm in cats, and the digits are the most common sites of metastasis. This case was unusual in that the skin of the abdominal wall was the primary site of metastasis, with no involvement of the digits.     

Epidemiology, diagnosis, and treatment of blastomycosis in dogs and cats

Blastomycosis is one of the most common systemic fungal diseases in dogs in North America, but it is rarely diagnosed in cats. The typical route of infection is inhalation of aerosolized conidia of Blastomyces dermatitidis. From the respiratory tract, the developing yeast form may disseminate throughout the body and affect multiple organ systems, most commonly the lymphatic, skeletal and central nervous systems, eyes and skin. Disseminated disease often is associated with nonspecific signs of illness including lethargy, inappetence and fever, as well as signs referable to specific organ systems like chronic cough and dyspnea, peripheral lymphadenopathy, endophthalmitis, and central nervous signs. Diagnosis is typically made by detection of Blastomyces dermatitidis yeast in affected tissues by fine-needle aspiration cytology or histopathology. The treatment of choice is itraconazole. Prognosis is fair in dogs without central nervous disease and guarded in cats.     

Comparison of 3 techniques for ureteroneocystostomy in cats

OBJECTIVE: To compare 3 techniques for ureteroneocystostomy in cats. STUDY DESIGN: Experimental surgical study. ANIMALS: Fifteen adult cats. METHODS: Cats (15) had ureteroneocystostomy with ureteronephrectomy of the contralateral kidney: 5 cats had an intravesical mucosal apposition technique (modified Leadbetter-Politano; intravesical-MA group), 5 cats had extravesical ureteroneocystostomy (modified Lich Gregoir) using a simple continuous suture pattern (extravesical-SC group) and 5 cats had an extravesical technique using a simple interrupted suture pattern (extravesical-SI group). Renal function was evaluated by measuring serum creatinine concentration. Ultrasonographic assessment of the kidney and ureteroneocystostomy site was performed the day after surgery, twice weekly for 3 weeks and once weekly for the remainder of the study. Cats were euthanatized 50 days after surgery. The kidney and ureter removed at surgery, the remaining kidney, ureter, ureteroneocystostomy site, and bladder were examined histologically. RESULTS: Two extravesical-SC cats were euthanatized because of azotemia and uroabdomen, and 1 died acutely at day 4 for unknown reasons. In the intravesical-MA and extravesical-SI cats, the serum creatinine concentration increased after surgery, peaking at a mean (+/-SD) of 9.4+/-2.4 mg/dL and 4.9+/-3.3 mg/dL on day 3, and decreasing to 3.4+/-5.7 mg/dL and 1.5+/-0.4 mg/dL on day 7, respectively. The extravesical-SI technique was associated with consistently lower serum creatinine concentrations for the first week after surgery compared with the other techniques. The mean serum creatinine concentration was within the reference range in cats in the intravesical-MA and extravesical-SI groups by days 10 and 5, respectively. Renal pelvic dilatation occurred in all cats but resolved more rapidly in cats after extravesical techniques. There was no significant difference in serum creatinine concentrations or renal pelvic dilation between the intravesical-MA and extravesical-SI techniques. Bladder mass height at the anastomosis site was significantly larger and persisted for longer with intravesical-MA technique. CONCLUSION: An extravesical-SI technique is seemingly the choice for ureteroneocystostomy in cats with undilated ureters. Renal pelvic dilation on ultrasound examination should be expected after ureteroneocystostomy in cats. CLINICAL RELEVANCE: An extravesical ureteroneocystostomy technique using a simple interrupted pattern for anastomosis should be considered in cats undergoing renal transplantation.     

Evaluation of 2 cement techniques for augmentation of stripped 1.5 mm screw sites in the distal metaphysis of feline radii

OBJECTIVE: To evaluate the effect of 2 cement augmentation techniques on pullout strength of 1.5 mm screws placed in stripped 1.5 mm screw sites in the distal metaphysis of feline radii. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Feline radii (21 pairs). METHODS: Treatment groups (n=4) were allocated according to a Latin square design to 4 sites in each pair of radii. Positive and negative controls were a 1.5 mm screw and a screw of the same diameter in a previously stripped screw hole, respectively. Treatment groups were a 1.5 mm screw implanted in a previously stripped screw hole after injection of polymethylmethacrylate (PMMA) or a bioresorbable calcium phosphate cement (CPC, Norian skeletal repair system (SRS)). The ultimate pullout strength was compared between groups. RESULTS: The mean (+/-SEM) pullout strength of screws augmented with either bone cement was less than that of the positive control group and greater than that of the negative control. Injection of CPC or PMMA before screw implantation increased the pullout strength of the negative control by 86.8+/-22.9% and 104.1+/-32.1%, respectively. Holding power of the positive control screws differed from these 2 groups, and was 274.8+/-39.17% higher than that of the negative control. CONCLUSION: Injection of CPC or PMMA increases but does not restore the holding power of stripped 1.5 mm diameter screws. CLINICAL RELEVANCE: The use of CPC (Norian SRS) augmentation of stripped 1.5 mm diameter screws warrants clinical investigation as it combines biomechanical results similar to PMMA with osteoconduction and resorbability.     

The effects of bimatoprost and unoprostone isopropyl on the intraocular pressure of normal cats

OBJECTIVE: To evaluate the effects on intraocular pressure (IOP), pupillary diameter (PD), blepharospasm score, conjunctival injection score, and aqueous humor flare score when either 0.03% bimatoprost solution is applied once daily or 0.15% unoprostone isopropyl solution is applied twice daily topically to the eyes of normal cats. MATERIALS AND METHODS: The aforementioned parameters were evaluated daily in each of 12 cats throughout the entirety of the study. During an initial 10-day treatment phase a single eye of six of the cats was treated with 0.03% bimatoprost solution while a single eye of the remaining six cats was treated with buffered saline solution (BSS) once daily. During a second 10-day treatment phase a single eye of six of the cats was treated with 0.15% unoprostone isopropyl solution while a single eye of the remaining six cats was treated with BSS twice daily. Contralateral eyes of all cats remained untreated at all time points. RESULTS: Blepharospasm score, conjunctival injection score, and aqueous humor flare score never rose from a value of 0, for any eye of any cat during the study. The mean +/- SD of IOP for eyes treated with 0.03% bimatoprost solution and BSS were 16.55 +/- 3.06 mmHg and 18.02 +/- 3.52 mmHg, respectively. The mean +/- of PD for eyes treated with 0.03% bimatoprost solution and BSS were 5.7 +/- 1.57 mm and 6.39 +/- 1.78 mm, respectively. The mean +/- SD of IOP for eyes treated with 0.15% unoprostone isopropyl solution and BSS were 15.7 +/- 2.91 mmHg and 17.2 +/- 2.9 mmHg, respectively. The mean +/- SD of PD for eyes treated with 0.15% unoprostone isopropyl solution and BSS were 5.8 +/- 1.43 mm and 6.9 +/- 1.37 mm, respectively. There was no significant difference (P > or = 0.05) in IOP or PD between eyes treated with 0.03% bimatoprost solution vs. eyes treated with BSS. Similarly, there was no significant difference (P > or = 0.05) in IOP or PD between eyes treated with 0.15% unoprostone isopropyl solution vs. eyes treated with BSS. CONCLUSION: Neither once daily topical administration of 0.03% bimatoprost solution nor twice daily topical administration of 0.15% unoprostone isopropyl solution significantly affect the IOP of normal cats. Both 0.03% bimatoprost solution and 0.15% unoprostone isopropyl solution induced no significant ocular side effects in normal cats when dosed over a 10-day treatment period.     

Histoplasmosis in dogs and cats

Histoplasma capsulatum is endemic throughout most of the United States with a high prevalence of infections in the Midwest and South. Histoplasmosis is the second most common systemic fungal disease in cats that may be more susceptible than dogs. Infection occurs by inhalation of conidia from the mycelial phase, which subsequently convert to the yeast form. Histoplasma capsulatum is phagocytized and harbored by cells of the mononuclear phagocyte system. Infection may be subclinical or cause clinical pulmonary granulomatous disease or dissemination. Disseminated disease predominantly affects the liver, spleen, gastrointestinal tract, bone and bone marrow, integument, and eyes. Primary gastrointestinal histoplasmosis also occurs. Clinical signs of histoplasmosis often are nonspecific, including chronic wasting, fever, anorexia, respiratory signs, and lameness. Gastrointestinal signs (eg, diarrhea with hematochezia or melena) are common in dogs. The definitive diagnosis is made by identification of the yeast in tissue samples. Itraconazole is the treatment of choice.     

TENESMUS AND STRANGURIA FROM A CYSTIC UTERINE REMNANT

A 14-year-old domestic short hair spayed female cat was examined for tenesmus and stranguria. The abdominal mass discovered was removed and found to be a cystic uterine remnant. Tenesmus and stranguria resolved following mass removal.     

DIAGNOSIS OF CALCIFICATION ON ABDOMINAL RADIOGRAPHS

A wide variety of normal and pathologic factors may induce intraabdominal calcification. In general, the most reliable indication of the cause of a calcification is its location; therefore, if the affected organ can be identified the radiographic diagnosis is often straightforward or, at least, limited to relatively few possibilities. With this principle in mind, a series of patients with abdominal calcification are described for the purpose of illustrating the appearance of calcification of various abdominal organs. In addition, etiology for the calcification in each patient is discussed. Certain extraabdominal calcifications which may be seen on abdominal radiographs are also mentioned.     

Two techniques for supplementing interlocking nail repair of fractures of the humerus, femur, and tibia: results in 12 dogs and cats

OBJECTIVE: To describe 2 devices for improving stabilization of inadequately stabilized interlocking nail (ILN) repairs of the humerus, tibia, and femur in dogs and cats. STUDY DESIGN: Prospective study. ANIMALS: Twelve client-owned dogs and cats. METHODS: Two devices to further stabilize ILN repair of inadequately stabilized diaphyseal fractures were developed. Device 1 was an axial extension for the ILN that was connected to a conventional type I external skeletal fixator (ESF) with a short connecting bar. Device 2 had hybrid ILN bolt/ESF pins that were used to lock the ILN and serve as the pins for a type I ESF. Devices were used at the initial surgery when the stability of ILN repair was considered inadequate based on palpable fracture segment movement, insufficient medullary canal filling of the ILN at the fracture site, or when the ILN was used in a buttress mode. Outcome was obtained by recheck examinations, radiography, and telephone interview. RESULTS: Device 1 was applicable to fractures of the humerus and femur, but was not used for fractures of the tibia because the ILN extension would have interfered with the stifle. No gross loosening of the ILN/ESF extension connection to the ILN occurred. Device 2 was easily placed and used in the humerus, femur, and tibia. Device 2 allowed removal of the ILN interlock to one or both main fracture segments non-invasively. Clinically, both devices added stability compared with ILN repair alone. Both devices facilitated controlled destabilization of the fracture repair as healing progressed. Complications of pin tract infection, and premature hybrid bolt/ESF pin loosening resulting in premature ESF removal each occurred in 1 patient. Four of 28 hybrid ILN/ESF pins were grossly loose at 4- or 6-week postoperative recheck examinations. Outcomes were excellent (9), good (1), fair (1), and poor (1). CONCLUSIONS: Inadequately stabilized ILN repair of fractures can be stabilized by use of either device, both of which also permit controlled destabilization of the repair during healing. Device 2 can be used when non-invasive removal of the ILN interlock is desired during healing. CLINICAL RELEVANCE: These 2 devices should be considered as alternative methods for stabilization of inadequately stabilized ILN repairs in dogs and cats, or when controlled destabilization of an ILN fracture repair is desired.