By Cathy Lewis
(copyright reserved to the author 2008)
I am not a veterinarian, nor do I represent myself as one on the internet. But I hope that my experiences as a Springer lover might be helpful to someone else in addressing grass awn symptoms in their working dog.
We have had four of our own dogs suffer grass awn infections, one with two separate incidents. Jessie and Tai have had surgeries for pyothorax, Tai and Roz have had abscesses removed. When Tigger showed clear symptoms of a pyothorax in 2007, we made the very difficult decision not to treat him because his age and general health suggested that he would not have a positive outcome. Actually, when I dig even further back in my memory, we had two other dogs that were treated for localized abscesses with drains and antibiotics (one later developed a fullblown pyothorax). When the abscess issue first cropped up, this seemed the more normal course of treatment, but perhaps this was more a lack of knowledge of the full extent of the problem than a different syndrome. Knowing what I know now, I’m not sure I would feel that this approach was aggressive enough in light of our subsequent experiences.
The increase in the number of grass-awn related infections appears to coincide with the increase in planting of Canada wild rye in conservation mixes in approximately 2001. Seeds recovered from two dogs in Minnesota in 2007 were determined to be Canada wild rye. Several additional samples recovered from dogs in Wisconsin were recently submitted for identification.
I have provided details of symptoms and treatments of our own dogs below. Here are the points that I would stress to anyone who thinks their dog might be affected by a grass awn. First, be aware that the symptoms of a grass awn infection can be very vague and nonspecific. It’s very important to be aware of your dog’s behavior, both when s/he is healthy and when s/he is not. If you have concerns that your dog just isn’t him or herself, consider a visit to your veterinarian and make sure that your concerns are taken seriously. These infections can go from barely noticeable to critical in an extremely short period of time. Many veterinarians, particularly those east of the Mississippi that do not have exposure to foxtail infections on a regular basis, or who do not have a lot of working dog clients, will not have a grass awn infection high up on their diagnostic radar. Your dog surviving a grass awn infection may well depend on you being an observant and informed owner, and you may need to educate your veterinarian. Refer him or her to the Grass Awn Project website and/or print out one or more of the articles from the site to put in your file, preferably before you have urgent need of that information.
Roz, 2008, Abscess:
Our most recent case of grass awn infection involved Roz, Edwardiana Rhapsody of Beggarbush, a 4 year old female. Roz ran a temperature of approximately 104 degrees at Thanksgiving, 2007, and showed discomfort in her back. Roz usually likes to put her feet up on me to be petted, but she began to avoid doing that and didn’t want to make the short jump into the dog trailer to go training. At that point I believed that Roz had not been exposed to grass awns, so we treated with doxycycline and her symptoms resolved. She showed the same symptoms in late January, 2008, so we did a full workup for a “fever of unknown origin” and suspected a urinary tract infection. A Lyme’s test was negative. With no other clues at that time, we again treated with doxycycline, and once again the symptoms disappeared. I found an abscess on Roz’ right side to the rear and at the base of her ribcage the evening of April 14th. We had trained earlier that evening and Roz ran enthusiastically. She did not have a fever nor did she seem ill. At my request, the following day our vet referred us to the University of Wisconsin, Madison veterinary school to address the abscess. Roz’ abscess was in a similar area, but the opposite side, from one that Tai had almost exactly a year previous, which was also treated at UWM (more later). Roz had a CT scan prior to her surgery that showed an “area of concern” in her back, along with the abscess on her side. Her surgery involved removing a piece of a back muscle (approximately 1” x 3”) – a grass awn was found and removed in this area – and removal of the abscess, which necessitated removal of two ribs and insertion of a piece of mesh to close the abdominal wall.
Roz had surgery on Thursday, April 17th. She came home on Sunday evening, April 20th. She was wearing a pain patch and was prescribed Rimadyl twice daily. Considering the extent of her surgery, she was fairly bright when she came home, and did well the next two days, eating with enthusiasm and happy enough to take brief walks on lead. Some fluid was pooling on her side in the area of her incisions. Per instructions I removed her pain patch Tuesday night. Wednesday morning Roz refused her breakfast. Her temperature remained normal. I took her to my vet to have the fluid pocket checked. It was large and heavy enough that it was dragging on the top staples closing her larger incision and pulling them loose. My vet was reluctant to attempt to drain the seratoma due to concerns about creating an opening for infection to enter. The seratoma had increased in size on Thursday and Roz was still not interested in food, so I took her back to UWM to see her surgeon. Roz was reassessed and the fluid pocket drained. We were concerned that her lack of appetite and slight depression was due to pain, so the surgeon prescribed a new pain patch and oral pain medication for 24 hours until the patch took full effect. Roz seemed to feel much better after these procedures, and resumed eating. Her recovery proceeded smoothly after this.
Culture results of the tissue removed during Roz’ surgery showed actinomyces and bacteroides. Actinomyces is part of the normal flora of the mouth, bacteroides of the intestinal tract (see http://microbewiki.kenyon.edu/index.php/Bacteroides, particularly the pathology section). While these bacteria are normal residents in various parts of the body, when they end up in other, “foreign” places, they wreak havoc. Based on these culture results I am suspicious that Roz may have swallowed the grass awn that caused her infection by migrating out of the intestinal tract. Roz was treated with Clavamox for two weeks post surgery, followed by two to three weeks of metronidazole after the culture results came back.
Roz’ surgeon believes that Roz should be able to return to trialing. Even with the loss of the two ribs her major organs remain adequately protected, though we would not want her to have any direct jabbing blows to that side. She’s back to taking daily free runs in the field four weeks post surgery. The suspensory ligament supporting the right ovary had to be cut and reattached during her surgery to access the infection in her back and remove the grass awn, so it remains to be seen whether she will have any reproductive repercussions from her procedure.
Tai, 2004-2005, Pyothorax:
Tai had bacterial pneumonia in his right lung in September (2004), but apparently recovered well after antibiotic therapy. He resumed running trials. On Thanksgiving evening, he presented with an abscess low on his right side, about level with and just behind his elbow. By the next morning when I got him to the clinic, the abscess had flattened out against the chest wall, so there wasn't much to do but watch it, and he took Clavamox for three weeks. As luck would have it, we were supposed to leave that day to compete in the National Open, and happily we did go to Kansas and Tai earned a Certificate of Merit in the trial.
In January (2005) I noticed that Tai had a small lump, about the size of a grape, that felt like it was on the bottom of a rib bone, a few inches back from where he had the abscess in November. On January 19th the lump was removed, and sent for a biopsy and culture. Our vet did find a splinter of plant material (more rigid than a grass seedhead, about 1/4 inch long) embedded in the lump. He did not find evidence of migration around the site, but was reluctant to do too much exploration for fear of causing a pneumothorax. That culture grew both actinomyces and nocardia. Tai was on Clavamox for several weeks, switching to three weeks of doxycycline as that was thought to be more effective against nocardia. Tai developed a hematoma/seratoma at the surgery site, but that healed without apparent complication.
In mid-March (2005) Tai suddenly presented with a fever (104.6 at the clinic) - this after training normally the day before. He carried himself with obvious discomfort, with his back arched like a whippet and what seemed like some vague lameness on his front feet. A chest x-ray was clear, and blood work was normal, as was a Snap test to rule out Lyme's disease. The vet sent us home with Clavamox again. It took about four days for his temperature to come back to normal, even on the antibiotics. No sign of external abscess with this episode. My concerns about actinomycosis and the possibility that the lameness might be osteomyolitis led me to request that the vet x-ray his left front leg that Monday; those x-rays were clear.
I had Tai entered in Master at the West Allis Training Kennel Club test Memorial Day weekend. He didn’t seem entirely himself that morning, but when he thought we were going training, he was happy enough to jump in the car. He didn’t run at all like himself, though, and when I took him back to the car I realized that his breathing was extremely labored. I immediately called my vet clinic and got him over for examination. A chest x-ray showed congestion in his chest, and our vet referred us to the University of Wisconsin, Madison. Tai was diagnosed with and successfully treated for a pyothorax, which included placing chest drains and periodic flushing of his chest for several days. His treatment notes from UWM are attached. Happily he made an apparent full recovery and resumed his trial career.
Tai, 2007, Abscess:
I found a lump on Tai's rib cage March 27. Roughly the size of half an egg but flattened out more, on the lower part of the last ribs on his left side. His previous abscess and lump were on the right side. Temperature normal, and he trained well the previous night. No other symptoms that I could observe. Lump slightly larger the next morning, which wasn't surprising especially since I'd compressed it the evening before and repeated that morning. The vet aspirated and took some fluid, no bacteria observed, just lots of white blood cells indicating infection. No indication that he had any chest congestion, thankfully.
My vet suggested antibiotic therapy, so we put Tai on clindamycin, which didn’t do much to change the size of the mass. He was rechecked on April 11, and on April 26 when his antibiotic was changed to Clavamox, which did seem to have some effect in reducing the size of the lump. We took him to University of Wisconsin, Madison on May 1. They took x-rays and did an ultrasound, which showed that he actually had two masses. I had been monitoring the one on the outside of the chest wall, but he had a second one inside the abdominal wall in the same general area. From the ultrasound it appeared that the masses were fairly encapsulated. The two masses were on either side of his abdominal wall like a sandwich around his ribs, so the bottom few inches of the last few ribs were removed along with the masses on May 2. At the time this seemed drastic to me - seems like those bones are where they are for a reason. Imagine how I felt when I got the report on the complete removal of two of Roz’ ribs a year later.
A grass awn was recovered from one of the masses.
Tai was originally scheduled for discharge on May 3rd, but his surgeon was concerned about the extent of his pain level so opted to keep him another day. He was feeling amazingly good by the time he came home on May 4th, but pain medication was prescribed to be sure he was comfortable. His activity was restricted for three weeks post surgery, and he was more than ready to get back to work at that time.
I have found conflicting information in my research as to whether it is prudent with these abscess cases to do some antibiotic therapy prior to surgery to attempt to reduce the abscess. I would discuss this thoroughly with your veterinarian if your dog develops an abscess.
This article will be updated periodically, and I have two additional case histories to write up once I’ve gathered the details .