Esophageal dysfunction in a weanling thoroughbred

A 6-month-old Thoroughbred colt was examined because of persistent dysphagia noted since birth. Moderately severe regurgitation occurred when the colt ate semi-solid food or drank. Complete esophageal impaction developed when the colt ate solid material. Endoscopic examination revealed ulceration, dilatation and lack of peristalsis in the area of the previous impaction. Barium esophagram demonstrated the dilatation in the area of the previous impaction. Esophageal manometry revealed prolonged simultaneous contractions throughout the esophagus suggesting the presence of a motor abnormality. The colt was maintained on a slurry of complete pelleted feed, but the esophageal dysfunction persisted until euthanasia at 17 months of age. Gross post mortem and histologic examinations showed no abnormalities in the muscularis mucosa, myenteric plexus, vagus nerve, or brain stem. The history, signs, and manometric findings suggested esophageal dysfunction in this colt. Motor disorders of the esophagus should be considered in horses with persistent dysphagia or recurrent episodes of choke and esophageal manometry can help characterize these disorders.     

Rhodococcus equi pneumonia in foals

Rhodococcus (Corynebacterium) equi pneumonia is diagnosed by thoracic auscultation, radiographic and hematologic examination, and transtracheal aspiration. Treatment may be unsuccessful because of the organism's tendency to cause pulmonary abscesses. A 2-month-old, depressed, anorectic, febrile Quarter Horse colt, previously unresponsive to penicillin therapy, had loud, moist breath sounds in the ventral lung fields. Chest radiographs revealed pneumonia. Based on culture and sensitivity tests on organisms isolated from transtracheal washes, chloramphenicol and erythromycin, and then oral trimethoprim-sulfadiazine, were given, in addition to supportive therapy. The animal was fully recovered within 2 months.     

Pneumocystis Pneumonia in a Thoroughbred Racehorse

Pneumocystis pneumonia is an opportunistic respiratory infection that occurs in immunocompromised animals. In horses, pneumocystic pneumonia is observed mostly in foals and often progresses rapidly. Here, we report pneumocystic pneumonia in a Thoroughbred racehorse. A 3-year-old Thoroughbred racehorse colt had marked respiratory symptoms for 3 weeks and was unresponsive to antibiotic treatment. At necropsy, firm, tan, patchy lesions were scattered diffusely in the lungs. Microscopically, alveolar septa thickened by proliferation of collagen fibers and infiltration of inflammatory cells were observed. In the alveolar spaces, many brown-black yeast-like organisms similar to cystic forms of Pneumocystis carinii were recognized by staining with Gomori's methenamine silver. Bronchoalveolar lavage fluid (BALF) obtained before necropsy included macrophages engulfing the fungus bodies. Amplified products were obtained from BALF and lung tissue samples by Pneumocystis-specific nested PCR. Phylogenetic analysis based on the 18S rRNA gene sequence revealed that the P. carinii organism from BALF was related to the Pneumocystis spp. detected in other animals and was especially close to P. carinii derived from ferrets. This is a rare case of pneumocystic pneumonia in a colt with chronic pulmonary lesions.     

Transient hypogammaglobulinaemia of the young in a Thoroughbred yearling

A 12-month-old Thoroughbred colt was presented for chronic recurrent respiratory disease characterised by persistent nasal discharge, intermittent pyrexia and coughing of several months' duration. These episodes were responsive to empirical antimicrobial therapy but returned once therapy was discontinued. History, physical examination and initial diagnostics were suggestive of bacterial pneumonia and possible underlying immunodeficiency. Serum immunoglobulin analysis and peripheral blood lymphocyte phenotyping revealed low serum IgG and IgM concentrations. In this 12-month-old colt, low serum IgG concentration was the most diagnostic parameter and supported a presumptive diagnosis of transient hypogammaglobulinaemia of the young. The colt responded favourably to repeated treatment with antimicrobials for bacterial pneumonia, and serial immunologic testing over the following months showed gradual increase in serum IgG and IgM concentrations, supporting the diagnosis of delayed development of humoral immunity in this patient.     

Pharyngeal trauma from endotracheal intubation in a colt

A pharyngeal performation, probably associated with endotracheal intubation, occurred in a healthy 4 1/2-month-old colt. Inhalation anesthesia was carried out for elective surgery, but acute cervical cellulitis, pleuritis, and pneumonia developed after the surgery. Antibacterial and supportive therapy was ineffective.     

Use of dapsone in the treatment of Pneumocystis carinii pneumonia in a foal

A 6-month-old male Quarter Horse was evaluated for chronic respiratory tract disease. Diagnostic investigations revealed pulmonary inflammation; Pneumocystis carinii was detected within macrophages. Lymphocyte subpopulation phenotyping and immunoglobulin concentration analysis were performed and results suggested immune suppression. Trimethoprim-sulfamethoxazole administration was initiated; the colt was discharged but was reexamined 8 days later because of profuse diarrhea and endotoxemia. Bacterial culture of feces recovered Salmonella spp resistant to trimethoprim-sulfamethoxazole, and a diagnosis of antimicrobial-associated colitis was made. Bilateral fibrinous hypopyon developed and was treated with topical medication and intracameral injections of human recombinant tissue plasminogen activator. Dapsone (3 mg/kg [1.4 mg/lb], PO, q 24 h; dose extrapolated from human data) was administered for treatment of P carinii pneumonia (56-day treatment period). The colt recovered from the pneumonia and diarrhea. Dapsone may be a useful adjunct to traditional treatment for P carinii pneumonia in horses or as a sole medication for horses that cannot tolerate other treatments.     

Midsagittal intraarticular fracture of the third phalanx in a colt

A 6-month-old Quarter Horse colt, with severe left foreleg lameness of 6 weeks' duration, had swelling of the distal interphalangeal joint and a smaller-than-normal left front foot. Radiographs revealed a nondisplaced, midsagittal, intraarticular fracture of P3, which was treated with an eggbar shoe with 2 quarter clips, and stall rest for 10 weeks. The colt was sound after 10 weeks.     

An outbreak of acute pneumonia in young, single-suckled calves.

An outbreak of acute severe pneumonia which affected six to 14-week-old single-suckled calves, resulted in 45/77 requiring treatment. The examination of paired sera from all affected calves revealed that neither an adenovirus, non infectious bovine rhinotracheitis virus nor parainfluenza 3 virus was involved. The acute exudative interstitial pneumonia found at post mortem was typical of pneumonic pasteurellosis.     

黄牛吸入性异物肺炎的诊治

黄牛吸入性异物肺炎,是因吸入尘埃、饲草和刺激性气体或灌药误入气管所致的以剧烈咳嗽为特征的肺部疾病。论文通过对一起群发本病的重危病例临床诊治,认为抓住最佳治疗时机与实施合理的治疗方案,对于避免急性死亡、控制病情恶化和实现康复颇有意义。     

Chronic granulomatous pneumonia and lung rupture secondary to aspiration of activated charcoal in a French Bulldog

A 4‐year‐old, spayed female French Bulldog was presented for respiratory distress and suspected aspiration pneumonia after oral administration of activated charcoal for possible ingestion of a suspected toxic dose of trazodone. The patient had a moderate volume of pleural effusion, which contained free and intracellular black particulate matter consistent with charcoal. Due to presumed charcoal aspiration with subsequent lung rupture, the right middle and right caudal lung lobes were surgically removed. Histology revealed abundant black debris consistent with charcoal and severe granulomatous inflammation. Based on the clinical, gross, and histologic findings, a diagnosis of severe, chronic, locally extensive, aspiration pneumonia and lung rupture with secondary pleuritis and mediastinitis due to charcoal aspiration was made. Aspiration pneumonia is the main complication of activated charcoal administration, which can incite extensive, granulomatous inflammation in the respiratory tract. To the authors’ knowledge, this is the first report describing the cytologic and histologic findings associated with inadvertent charcoal aspiration in a veterinary species.     

Diagnosis of pneumocystis pneumonia in a 2‐year‐old King Charles Cavalier Spaniel using the polymerase chain reaction

A 2‐year‐old, female spayed, King Charles Cavalier Spaniel was presented for evaluation of dyspnea, inappetence, and lethargy. Thoracic radiographs revealed a moderate diffuse interstitial lung pattern affecting the perihilar and caudodorsal lung fields, and an echocardiogram revealed severe pulmonary hypertension. A bronchoalveolar lavage (BAL) was performed, and cytology revealed mixed inflammation with cysts and trophozoites consistent with Pneumocystis. Pneumocystis infection was later confirmed with PCR. To the author's knowledge, this report represents the first case of canine pneumocystis pneumonia diagnosed antemortem with PCR from a BAL sample. Pneumocystis represents an important, but uncommon cause of afebrile pneumonia in immunosuppressed dogs.     

Observations on outbreaks of respiratory disease in calves associated with parainfluenza type 3 virus and respiratory syncytial virus infection.

In four outbreaks of indoor calf pneumonia, dyspnoea was a prominent clinical finding. At necropsy it was associated with pneumonia involving the cranial lobes of the lung and severe pulmonary emphysema. Histological examination of lung tissue revealed bronchiolitis and alveolitis with alveolar epithelial cell hyperplasia and multinucleate syncytium formation. Intraalveolar haemorrhage, intra-alveolar oedema and hyaline membrane formation were also noted. In all cases parainfluenza type 3 (PI3) virus was isolated from the lungs. In each of the four outbreaks there was evidence of PI3 virus and respiratory syncitial virus (RSV) infection.     

Effect of Intestinal Resection on Two Juvenile Horses With Granulomatous Enteritis

Two horses were presented with lethargy, weight loss, anorexia, and swelling of the limbs and ventral body wall. One horse, a 12-month-old American Paso Fino colt, also had acute abdominal pain. The other horse, a seven-month-old Tennessee Walking Horse (TWH) filly passed diarrheic stools during the initial examination. Each horse had low serum protein, neutropenia, and a normal packed cell volume (3.2 g/dl, 1300 cells/ul, and 38%, respectively, for the colt, and 2.4 g/dl, 696 cells/ul, and 44%, respectively for the filly). After intravenously administering plasma, the colt's PCV dropped to 23%, and the filly's dropped to 30%. During exploratory surgery, 3.5 and 2.0 meters of thickened terminal small intestine were removed from the colt and filly respectively, and a jejunocecostomy performed. The results of histologic examination of resected intestine were consistent with a diagnosis of equine granulomatous enteritis (EGE). Both horses showed clinical improvement within two days after surgery. The colt developed a neutrophilia (20,500 cells/ul) within 24 hours of surgery. Serum protein concentrations remained stable and gradually elevated to normal or near normal values of 7.0 g/dl (colt) and 5.8 g/dl (filly) by two weeks. The colt was killed four months after surgery because of signs of abdominal pain. Postmortem examination revealed a small intestinal volvulus associated with an adhesion. The TWH filly remains clinically normal 13 months after surgery.     

Pneumonia in a Paso-Fino mare

A 5-year-old Paso-Fino mare was presented for severe respiratory distress. The mare had foaled 2 months prior to presentation. The horse was in poor body condition with a dull hair coat. A mild fever was noted during physical examination and increased bronchovesicular sounds were auscultated. Thoracic radiographs showed an interstitial pattern and an alveolar infiltrate with distinct air bronchograms. Moderate purulent inflammation with increased mucus was observed in tracheal wash fluid, but no infectious agents were identified. A bronchoalveolar lavage (BAL) contained a large amount of mucus and reactive mononuclear phagocytes with variable numbers of intracellular fungal organisms morphologically consistent with Pneumocystis carinii. The mare had undetectable levels of immunoglobulin M (IgM) and decreased IgG levels in the serum. Immunophenotyping revealed decreased expression of major histocompatability complex (MHC) class II molecules. Moderate to marked hyperplasia of type II epithelial cells was present throughout histologic sections of lung, but the fungal organisms were not observed. A culture system has not been developed for diagnosis of P carinii infection. Instead, diagnosis of P carinii pneumonia is achieved by microscopic identification of characteristic morphologic features of the pathogen. Cytologic examination of BAL fluid is the preferred method used to diagnose human infection with P carinii. In humans, the diagnostic sensitivity of cytology is significantly higher than the sensitivity of histopathologic examination of lung biopsies. The difference in sensitivity between BAL cytology and lung histopathology may also apply to the diagnosis of P carinii pneumonia in horses. (MacNeill AL, Alleman AR, Franklin RP, Long M, Giguère S, Uhl E, López-Martinez A, Wilkerson M. Pneumonia in a Paso-Fino mare [ Pneumocystis carinii pneumonia].     

Surgical Repair of a Perforated Gastric Ulcer in a Foal

An 11-day-old Thoroughbred colt was presented because of acute colic and a swollen right carpus. Exploration of the abdomen revealed peritonitis secondary to a perforated gastric ulcer. The ulcer was repaired, and the peritoneal cavity was lavaged. The foal recovered from the perforated ulcer but was euthanized one and a half months later because of progressive septic arthritis.     

Effect of porcine reproductive and respiratory syndrome virus (PRRSV) on alveolar lung macrophage survival and function

Porcine reproductive and respiratory syndrome virus (PRRSV) recently emerged as an important cause of reproductive disorders and pneumonia in domestic pigs throughout the world. Acute cytocidal replication of PRRSV in alveolar lung macrophages causes the acute pneumonia; however, it remains largely unresolved whether there may also be a predisposition to longer-term local immunodeficiency in the PRRSV-convalescent lung. We applied various flow cytometric techniques to study the interplay between PRRSV replication and macrophage viability/function in pure cultures of porcine alveolar lung macrophages. Monitored by flow cytometric detection of intracellular PRRSV nucleocapsid protein, acute (24 h post infection) PRRSV replication did not impede the ability of alveolar macrophages to ingest fluorescently labelled Escherichia coli. At 48 h post infection, PRRSV-induced cytotoxicity (quantitated by flow analysis of cell size and membrane integrity) led to 40% reduction in the total number of phagocytozing cells. However, viable/uninfected macrophages in PRRSV-infected cultures exhibited normal phagocytic ability at 48 h, indicating that no soluble phagocytosis-suppressive mediators were induced by PRRSV infection in this system. In short, in our minimal system containing only a single cell type, phagocytosis-suppressive effects of PRRSV infection were detected, that acted at the culture level by reducing the total number of alveolar lung macrophages.     

Traumatic sacral fracture following dystocia in a Thoroughbred foal

A Thoroughbred colt with a history of dystocia was referred for further management of suspected hypoxia. The foal showed signs of neonatal maladjustment syndrome and hindlimb paralysis. Radiography revealed the presence of a severe lumbosacral injury. The foal was subjected to euthanasia due to a hopeless prognosis. Computed tomography was performed post‐mortem and revealed a type I Salter Harris fracture of the cranial physis of the first sacral vertebra.     

Nodular Pneumocystis carinii pneumonia in SIV-infected macaques.

Pneumocystis carinii (PC) pneumonia is a frequent manifestation of the acquired immunodeficiency syndrome (AIDS) in humans and macaques. An unusual nodular type of PC pneumonia was observed in two simian immunodeficiency virus (SIV)-inoculated rhesus macaques (Macaca mulatta). These animals developed clinical signs of simian AIDS, including anorexia, weight loss, dyspnea, and collapse. Grossly, both animals had multifocal tan-white nodules 1-10 mm in diameter scattered throughout the lungs. One animal had similar nodules involving the diaphragm and thoracic wall. The lungs were characterized by severe PC pneumonia with numerous large nodules consisting of foamy material that compressed adjacent tissue. The nodules had central areas of necrosis and lysis of alveolar septa. Varying degrees of necrotizing vasculitis were observed in areas of nodular PC pneumonia. The presence of PC in intra-alveolar spaces and nodular lesions was confirmed by immunohistochemistry. No evidence of other agents, including viral inclusions, bacteria, fungi, and lung mites, was detected. The animal with the most severe nodular PC pneumonia had vascular involvement with extrapulmonary spread to the diaphragm, thoracic wall, and regional lymph nodes. This unusual type of nodular PC pneumonia has been rarely seen in human AIDS patients.     

Bilateral degenerative suspensory desmitis with acute rupture in a Standardbred colt

A 3‐month‐old Standardbred colt was examined for acute, bilateral hindlimb swelling and lameness. Serum chemistry demonstrated elevated muscle enzymes (AST, ALT, LDH and CK). Radiographs of the hindlimbs demonstrated intact proximal sesamoid bones that were displaced distally and subluxation of the pastern joints. Ultrasonography of the affected areas revealed large, diffuse hypoechoic areas in the bodies of both hind suspensory ligaments consistent with bilateral rupture. Histology of the lesions was consistent with degenerative suspensory desmitis with acute rupture.     

IMAGING DIAGNOSIS—SPONTANEOUS PNEUMOMEDIASTINUM SECONDARY TO PRIMARY PULMONARY PATHOLOGY IN A DALMATIAN DOG

A 1.5‐year‐old, 23 kg intact male Dalmatian dog was evaluated for acute respiratory insufficiency without a previous history of trauma or toxic exposition. Imaging revealed pneumomediastinum, pneumothorax, diffuse unstructured interstitial pulmonary pattern, pulmonary interstitial emphysema, and pneumoretroperitoneum. Histopathological evaluation of the lungs revealed perivascular and peribronchial emphysema, mild lymphocytic interstitial pneumonia with atypical proliferation of type II pneumocytes in bronchioles and alveoli. A lung disease resembling fibrosing interstitial pneumonia in man and cats has been previously reported in Dalmatians and should be included as a differential diagnosis for Dalmatians with this combination of clinical and imaging characteristics.