Clinical management of a western lowland gorilla (Gorilla gorilla gorilla) with a cardiac resynchronization therapy device

A 24-yr-old, male western lowland gorilla (Gorilla gorilla gorilla) was diagnosed with congestive heart failure using transesophageal and transthoracic echocardiology. New York Heart Association (NYHA) Class III was assigned to the severity of the condition. Over 16 mo, this progressed to NYHA Class IV despite increasing medical therapy. Repeated evaluations suggested that implantation of a cardiac resynchronization therapy device with a defibrillator (CRT-D) could benefit this animal based on clinical signs and underlying evidence of dyssynchrony and suspected fibrotic myocardial disease. Surgical implantation of leads into the right atrium, right ventricle, and left ventricle was accomplished. The CRT-D device was placed under the thoracic pectoral muscles during an initial surgical procedure. Improvement in the gorilla's clinical condition after implantation of the CRT-D device was immediate and dramatic. Subsequent scanning of the device was accomplished through operant conditioning. The data from these device interrogations included stored and real-time cardiac data, which were used to minimize recognized environmental stressors and change device settings. Over 4 yr, case management was critical to successful device use in treatment of the clinical disease. This involved medications, training for device interrogation, exercise to increase activity and improve body condition, and phlebotomy attempts. Dietary management was necessary to manipulate caloric and sodium intake and encourage medication compliance. Cardiac resynchronization therapy device implantation, although requiring specialized equipment and surgical skill, appears to be a viable option for treatment of fibrosing cardiomyopathy with systolic dysfunction in gorillas refractory to medical management. In addition to treatment, this device provides cardiovascular data at rest that could allow for early diagnosis and treatment of gorillas with this and other cardiac conditions in the future. This describes the comprehensive medical, husbandry, and training techniques necessary to successfully manage this intense clinical case in conjunction with intracardiac device therapy.     

Severe idiopathic hypocalcemia in a juvenile western lowland gorilla, Gorilla gorilla gorilla

A 6-mo-old, male western lowland gorilla (Gorilla gorilla gorilla) was evaluated because of tetany of both hands. The gorilla had alternating periods of constipation, diarrhea, and bloating since birth. A diagnosis of idiopathic hypocalcemia was based on severe hypocalcemia, a normal vitamin D level, response to oral calcium and vitamin D therapy, and eventual resolution. Idiopathic hypocalcemia, an uncommon disease in neonatal humans, should be considered in young gorillas with persistent gastrointestinal problems or acute tetany.     

Chronic lymphocytic leukemia in the dog: 22 cases (1974-1984)

Chronic lymphocytic leukemia was diagnosed in 22 dogs. Diagnosis was based primarily on detection of lymphocytosis and bone marrow infiltration with small lymphocytes similar to those seen in the blood. More than 50% of the dogs had monoclonal gammopathy, and, of these, 40% had monoclonal light-chain (Bence Jones) proteinuria. Hyperviscosity syndrome was observed occasionally. Most dogs were treated with chemotherapy. For the 17 dogs treated greater than or equal to 30 days, the survival times ranged from 30 to 1,000 days.     

Management of reactive arthritis in a juvenile gorilla (Gorilla gorilla gorilla) with long-term sulfasalazine therapy.

A juvenile western lowland gorilla (Gorilla gorilla gorilla) experienced recurrent fever, lethargy, diarrhea, and/or arthritis starting at age 6 mo. During an episode at age 15 mo, Shigella sp. was isolated from diarrheic feces. At age 41 mo, reactive arthritis was diagnosed. In addition, the gorilla's growth was retarded. All arthritic attacks were managed symptomatically prior to age 4 yr, at which time a severe episode precipitated the implementation of therapy with sulfasalazine, an arthritis suppressive medication. Examination 27 mo later revealed cessation of progressive joint pathology although the animal exhibited decreased range of motion in most joints. The gorilla has been on sulfasalazine therapy for 4 yr without lameness. Growth has resumed, and there has been no radiographic evidence of progressive joint degeneration. Immunogenetic analysis of whole blood obtained at age 68 mo identified the gorilla major histocompatibility class I allele, Gogo-B*0101, which has limited nucleotide sequence similarity to HLA-B27, an allele associated with postinfection reactive arthritis in humans. Sulfasalazine therapy effectively managed reactive arthritis in this gorilla and should be considered for similarly frequently affected animals. Juvenile gorillas, in populations with a history of clinical shigellosis and/or postdiarrhea arthritis, may benefit from prophylactic sulfasalazine therapy after episodes of bacterial enterocolitis. Sulfasalazine therapy should be considered in all gorillas, juvenile and adult, experiencing confirmed Shigella sp.-associated enterocolitis.     

Resolution of a hyperprolactinemia in a western lowland gorilla (Gorilla gorilla gorilla).

Prolactin-secreting pituitary adenomas are one of the most common causes of infertility in women. Prolactin plays an important role in lactation and is involved in producing some of the normal mammalian breeding and maternal behaviors. Elevated serum prolactin concentrations can adversely affect the reproductive cycle in females by inhibiting the normal lutenizing hormone surge that stimulates ovulation. A 17-year-old western lowland gorilla (Gorilla gorilla gorilla) presented with low fertility and hyperprolactinemia. An MRI confirmed a pituitary mass and treatment was initiated with cabergoline. Following 8 mo of treatment, mass size decreased and serum prolactin was within normal limits. The gorilla began to engage in normal breeding behavior, and within 6 mo of completing treatment, was pregnant. Hyperprolactinemia, secondary to presumed microprolactinoma, may be more common among breeding-age gorillas than is currently diagnosed and in humans is an easily diagnosed and treatable condition.     

Chorionic villus sampling for sex determination in a western lowland gorilla (Gorilla gorilla gorilla).

Chorionic villus sampling was undertaken on an anesthetized gorilla (Gorilla gorilla gorilla) to determine the fetal sex in the first trimester of pregnancy. The tissue samples were subject to sex determination by polymerase chain reaction, fluorescent in situ hybridization, and cell culture with cytogenetic analysis. Polymerase chain reaction testing was found to be the most accurate and rapid method of sex determination on this tissue sample.     

Cataract surgery with foldable intraocular lens implants in captive lowland gorillas (Gorilla gorilla gorilla).

Two juvenile, male, captive-born lowland gorillas (Gorilla gorilla gorilla) with the same father but different mothers developed bilateral cataracts. The cataracts were surgically removed within 6 yr and 3 mo, respectively, of diagnosis, and foldable intraocular lenses were implanted. Although vision was not restored in one eye with a mature, 6-yr-old cataract in gorilla A, surgical intervention on the other eye was performed before a complete cataract developed, and vision was fully restored. Gorilla B was treated at the age of 17 mo, and normal visual development proceeded in both eyes. This animal developed bilateral after-cataract and therefore needed a second intervention in both eyes using Nd:YAG laser treatment. The genetic component of juvenile cataracts should be considered in breeding management programs.     

Chronic hypertension with subsequent congestive heart failure in a western lowland gorilla (Gorilla gorilla gorilla).

Chronic severe subclinical systemic hypertension was diagnosed in a 28-yr-old male western lowland gorilla (Gorilla gorilla gorilla). Thoracic radiography, electrocardiography, and echocardiography revealed an enlarged heart with a hypertrophied left ventricle, mitral regurgitation, and a persistent left bundle branch block. Enalapril, later combined with nifedipine, was of some value in reducing the hypertension, with partial reversal of cardiac enlargement and resolution of the bundle branch block. Two years after initiation of treatment, the gorilla developed lethargy and dyspnea. The diagnosis of heart failure was confirmed under anesthesia; the gorilla did not recover and was euthanized. Postmortem examination confirmed congestive heart failure with chronic, fibrosing cardiomyopathy similar to that in other gorillas.     

Diagnosis of hypothyroidism in a western lowland gorilla (Gorilla gorilla gorilla) using human thyroid-stimulating hormone assay.

Primary hypothyroidism was diagnosed in a 26-yr-old female western lowland gorilla (Gorilla gorilla gorilla) on the basis of serum levels of thyroxine (T4), free T4, and thyroid-stimulating hormone (TSH) measured by human immunoassays. Compared with clinically normal gorillas, the TSH level (107 mlIU/L) was markedly elevated, and T4 (<14.0 nmol/L) and free T4 (5.0 pmol/L) levels were decreased. Thyroid hypofunction could explain the weight gain, unsettled appetite, anxious behavior, lethargy, and poor intraspecies interactions shown by this gorilla. The antibodies in the commercial immunoassay used in this study apparently cross-reacted with gorilla TSH. Supplementation with levothyroxine sodium was initiated and was followed by a marked decrease in circulating TSH and a noticeable improvement in the animal's physiologic status and activity level.     

Clostridium septicum myositis in a western lowland gorilla (Gorilla gorilla gorilla).

A 10-yr-old male gorilla (Gorilla gorilla gorilla) with a history of conspecific bite wounds was evaluated for acute onset of depression, anorexia, and right hemiparesis. The animal was immobilized for diagnostic examination and treatment for suspected toxic shock from a necrotizing, emphysematous wound infection, but was euthanized due to complications during recovery. Gross and histopathologic examination revealed acute necrotizing myositis, fasciitis, cellulitis, and emphysema in the affected wound area, with large numbers of large Gram-positive rods among necrotic muscle fibers. Severe pulmonary edema with airways containing fibrin, acute hemorrhage in multiple body sites, thrombosis in blood vessels in the skeletal muscle, liver, and lung, and lymph node hyperplasia with lymphoid necrosis and hemorrhage. Immunohistochemical fluorescent antibody staining of muscle from the wound site was positive for     

Chronic lymphopenia and neutropenia in a dog with large granular lymphocytic leukemia

T‐cell large granular lymphocytic leukemia (T‐cell LGLL) is the most common presentation of chronic lymphocytic leukemia (CLL) in dogs. Aleukemic or subleukemic leukemia is a particularly rare variation in both humans and dogs, where bone marrow proliferation is either not or only sparsely translated in the peripheral blood. Neutropenia is a prominent feature in cases of human T‐cell LGLL but is normally absent in canine CLL. This report describes a case of a dog presented with an almost 3‐year history of asymptomatic neutropenia, lymphopenia, and thrombocytopenia (without anemia). A bone marrow examination, the exclusion of infectious diseases, and clonality testing led to the diagnosis of subleukemic LGLL that responded well to therapy (death occurred 2.5 years later due to an unrelated cause).     

Hydroxyurea-induced onychomadesis in a dog with chronic myeloid leukemia: A case report

A 12-year-old Rottweiler dog was presented with a history of prostration, weight loss and hyporexia for six months. Based on complete blood tests (hematological and biochemical analyses), bone marrow examination and imaging analysis, a diagnosis of chronic myeloid leukemia was made. Treatment with hydroxyurea at a dosage of 18?mg/kg twice daily was not effective in controlling the high count of white blood cells. Furthermore, after 35 days of hydroxyurea treatment, the animal developed onycholysis, with sloughing of the claws of the left pelvic and left thoracic limbs and exposure of the distal phalanx. Interruption of the medication was implemented, with clinical healing of the ungual lesions observed three months after initiation of the drug. White blood cells returned to normal after using cyclophosphamide. Currently, the animal is in complete remission, having a disease-free interval of 575 days without chemotherapy. To the authors' knowledge, this is the first report of hydroxyurea-induced onycholysis within a short-term period in a dog diagnosed with chronic myeloid leukemia.     

Suspected macular degeneration in a captive western lowland gorilla (gorilla gorilla gorilla)

The case of a 31-year-old captive female Western lowland gorilla (Gorilla gorilla gorilla) with decreased near vision but good distance vision is presented. Examination of the fundus revealed drusen-like bodies in the macula presumably because of an age-related macular degeneration (AMD).     

Hyperviscosity syndrome associated with lymphocytic leukemia in three dogs.

Hyperviscosity syndrome was associated with increased plasma content of monoclonal immunoglobulin (IgA or IgM) in 3 dogs with lymphocytic leukemia. The diagnosis of lymphocytic leukemia was based on the finding of a large number of mature lymphocytes in the blood and bone marrow. The clinical signs included weakness, lethargy, depression, and coughing due to congestive heart failure. Consistent physical findings were splenomegaly, with or without peripheral lymphadenopathy, and funduscopic abnormalities. Of the 2 dogs treated successfully with chlorambucil, 1 remains in remission after withdrawal of the drug for over 1 year.     

Ophthalmic examination of the captive western lowland gorilla (Gorilla gorilla gorilla).

This study examined the captive western lowland gorilla (Gorilla gorilla gorilla) eye as compared and contrasted with the human eye. Bilateral ophthalmic examinations of western lowland gorillas (n = 5) while under general anesthesia were performed opportunistically, including slit-lamp biomicroscopy, dilated fundus examination, cycloplegic retinoscopy, Schiotz tonometry, corneal diameter and thickness measurements, A-scan and B-scan ultrasonography, keratometry, and cultures of the eyelid margins and bulbar conjunctiva. Mean spherical equivalent refractive error by cycloplegic retinoscopy was +1.20 +/- 0.59 diopters. Mean intraocular pressure by Schiotz tonometry was 12.0 +/- 4.3 mm Hg. Mean optic nerve head cup to disc ratio was 0.42 +/- 0.11. Mean horizontal corneal diameter was 13.4 +/- 0.8 mm, and mean vertical cornea diameter was 12.7 +/- 0.8 mm. Mean central corneal thickness by ultrasound pachymetry was 489 +/- 52 microm. Mean axial length of the eye by A-scan was 22.75 +/- 0.71 mm. Mean lens thickness by A-scan was 4.23 +/- 0.34 mm. Mean anterior chamber depth by A-scan was 4.00 +/- 0.26 mm. Mean keratometry reading was 44.38 +/- 1.64 diopters. Eyelid margin and bulbar conjunctival cultures isolated Candida sp. (n = 5), Staphylococcus aureus (n = 4), Staphylococcus epidermidis (n = 3), Staphylococcus saccharolyticus (n = 3), and Micrococcus sp. (n = 3). This study suggests important similarities between western lowland gorilla and human eyes. These similarities may allow diagnostics, techniques, and equipment for human eye surgery, such as those used for cataract extraction and intraocular lens implantation, to be successfully utilized for gorillas.     

Comparative ocular anatomy of the western lowland gorilla

OBJECTIVE: To examine the lowland gorilla (Gorilla gorilla gorilla) eye and determine similarities to and differences between the mountain gorilla (Gorilla gorilla beringei) and the human eye. In addition, we compare our findings of G. g. gorilla to previous reports on the eye of this subspecies. PROCEDURES: A 13-year-old deceased male lowland gorilla and a 34-year-old deceased female lowland gorilla were included in the study. Gross and microscopic examinations of the formalin-fixed right eyeball of each gorilla were carried out. RESULTS: Globe dimensions of G. g. gorilla were similar to G. g. beringei and to humans. The limbal conjunctival epithelium and the choroid were densely pigmented. However, the distribution of the conjunctival pigment ring was different to that of G. g. beringei and the melanocytes of the choroid were unusually round. There were deep crypts in the anterior border layer of the iris, and the epithelium of the pars plana was uniquely irregular. Vertical corneal diameter was observed to be equal or greater than horizontal diameter in G. g. gorilla, which is in contrast to humans and to previous findings for G. g. beringei. Corneal thickness was closer to that of humans than to G. g. beringei. Posterior lens capsule thickness was noticeably greater than that of humans. CONCLUSIONS: Although some variation between the ocular anatomy of G. g. gorilla and G. g. beringei does exist, the gross and microscopic findings closely resemble each other in these two subspecies. In addition, the eye of Gorilla appears remarkably similar to the human eye. However, comparison of measurements with those in humans is somewhat limited because formalin-fixation can introduce tissue shrinkage and artifact.     

Acute respiratory failure caused by leukaemic infiltration of the lung of a dog

A seven-year-old crossbred male dog with a suspected leukaemic condition was referred for investigation and treatment. A bone marrow aspirate revealed an acute myeloid leukaemia. Combination chemotherapy was administered and the dog initially improved, but 18 days after the initiation of therapy its body condition deteriorated and the animal developed acute respiratory distress. On postmortem examination, extensive leukaemic pulmonary infiltrates were evident.     

Bone marrow hypoplasia associated with fenbendazole administration in a dog

A 1.5-year-old Doberman pinscher was presented with sudden-onset of fever and malaise. Twelve days prior to presentation, fenbendazole therapy was initiated for a suspected lungworm infection. Results of a complete blood count on presentation showed pancytopenia, while histopathological evaluation of a bone marrow core sample revealed bone marrow hypoplasia of undetermined etiology. Bactericidal antibiotics and fluid therapy, as well as discontinuation of fenbendazole administration, led to a complete resolution of clinical and hematological abnormalities within 15 days. An idiosyncratic reaction to fenbendazole was suspected based on the absence of infectious, neoplastic, autoimmune, and toxic etiologies, as well as resolution of clinical signs and pancytopenia upon drug withdrawal.     

A dog with acute myelomonocytic leukemia

A three-year-old dog with marked leukocytosis, lymphadenopathy, and diarrhea showed an increase in unidentified blasts in the peripheral blood, and they were proliferated in the bone marrow. The dog was diagnosed with myelomonocytic leukemia (M4) because the blast cells were demonstrated by cytochemical staining to be both myeloid and monocytic cells. Although the dog was treated with a multi-combination chemotherapy and induction therapy using vitamin K2, it died on day 47 after the first admission. This case is the first report of M4 in Japan.     

Gingival hyperplasia induced by diphenylhydantoin in a gorilla

An adult male lowland gorilla had been treated with diphenylhydantoin for 6 months following several acute convulsive episodes. The gorilla remained clinically normal during that period. Then, for no apparent reason, it refused its usual diet. Physical examination revealed acute inflammatory gingival hyperplasia. Full mouth gingivectomy and antibiotic and analgesic therapy resolved the oral inflammation and the anorexia.