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THIS MONTH 
Campylobacteriosis-The FACTS
Blood Typing and Transfusion
Next Clin Path Club meeting
Clin Path Club Dates for 2001
Hillarious Histories
DEFRA May only use UKAS Accredited Laboratories
Tail End: "Dogs are just people who wag their tails!"

Campylobacteriosis - the FACTS
“Campylobacter is part of the commensal flora of animals"

Campylobacteriosis is caused by a microaerophilic group of Gram-negative curved motile rods that can be part of the commensal flora of animals.

More research is needed to characterise pathogenic v nonpathogenic strains. It appears that the infective dose is quite low for humans, i.e. people are fairly susceptible and the young and immunocompromised are particularly susceptible.

Campylobacter can be isolated from apparently healthy animals but… Where there have been transmissions from animals to people the animals concerned have usually been diarrhoeic, often recently acquired from a kennel or pet store environment, or from a rescue shelter.

Uncooked meat, especially poultry, remains the most common source of infection for both animals and people.
The faecal-oral route is important in the kennel environment. The organism can also be transmitted via water.
At NWL, we are isolating Campylobacter from a low but increasing number of cases of diarrhoea in dogs and occasionally from cats. We notice that animals recently obtained from particular sources are more commonly positive emphasising that history can be helpful in deciding the course of a case work-up. Cases in cats were associated with the feeding of minced chicken from a pet store in one town. The prevention and eradication of Campylobacter infections can be a headache for those involved in rescue kennels, particularly as infections can occur concurrently with Parvovirus infection. Isolation of the organism from faeces will be increased where two or more samples taken at least 48 hour intervals are examined.

Severity of the disease is partly dependent on the number of organisms ingested. It ranges from loose watery faeces to bloody mucoid diarrhoea and can be an acute severe presentation through to a prolonged or recurrent problem over weeks or months. Occasional cases of cholecystitis associated with C jejuni infection have been recorded in dogs.

Isolation of the organism will almost certainly be prevented by prior antibacterial therapy, which can affect shedding. This is why we recommend a period of 10 days post treatment before retesting to check for elimination of the infection.

Where elimination of infection proves difficult, further examination for other bowel disease or immunosuppressive illness may be a consideration.

Where there is a risk of human infection, as was the case recently in a lap dog living in an old people’s home, simple hygiene measures should be advised. The instigation of antibacterial therapy (erythromycin is the treatment of choice) should quite quickly eliminate shedding of the organism.

Dr Geraldine Hale BVM&S PhD Cert PM MRCVS
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Canine Blood Typing
“Blood cross-matching should be considered prior to first transfusion"

In the dog, blood groups are classified according to dog erythrocyte antigen (DEA) system and to date six DEA’s have been identified, namely DEA 1.1, 1.2, 3, 4, 5 and 7.

Some of the antigens have more relevance than others, with DEA 1.1 and 1.2, which are alleles, being the most significant. This is because they are the most potent antigenically and are capable of provoking intense antibody production when transfused into a dog that does not possess them. DEA 1.1 is the more prevalent, has greater stimulating potential and is the major lytic factor in canine transfusion medicine. 

Naturally occurring antibodies directed against foreign canine blood groups, also known as alloantibodies, do not exist for DEA 1.1 and 1.2. The significance of this is that acute incompatibility reactions do not occur following the first transfusion of a DEA 1 negative recipient with DAE 1.1 or 1.2 positive blood will however subsequent antibody production will result in delayed red cell haemolysis and a significant reduction in the lifespan of the transfused red cells. Thereafter, such recipients are sensitised, any subsequent transfusion from the same, or any other DEA 1.1 or 1.2 positive donor, would result in an acute, life threatening reaction.
Most commercial assays for canine blood typing only give information as regards the DEA 1.1 status. Full blood typing may be available at certain reference laboratories but is rarely performed in a clinical situation.
Statistically approximately 40% of dogs are thought to be DEA 1.1 positive. Some breed trends have been observed with Labradors, Golden Retrievers and Rottweilers, tending to be DEA 1.1 or 1.2 positive. Greyhounds and German Shepherd Dogs are more likely to be negative for the DEA 1 group and can generally be thought of as “ideal donors”.

Recently a third allele, DEA1.3, has been described. DEA1.3 positive dogs are 1.1 and 1.2 negative and so appear to be ideal donors. However, if their blood is transfused into a 1.1 or 1.2 negative recipient, antibodies will be raised against DEA 1.1, 1.2 and 1.3 antigens. The end result is a 1.1 and 1.2 negative recipient being sensitised by a 1.1, 1.2 negative donor! The prevalence of DEA 1.3 dogs is not clear and is likely to be quite low but this does highlight the importance of cross-matching any patient who has previously been transfused, even when the blood type of the donor is “known”.

Briefly, considering the other blood groups, post transfusion sensitisation will occur if a negative dog is transfused with DEA 3, 5 or 7 blood. In addition, alloantibodies exist in a certain number of dogs. Antibodies to DEA 3, 5 and 7 are thought to cause delayed haemolysis, however, the incidence of such reactions is believed to be low, and these groups are of relatively minor significance in canine transfusion medicine.
The majority of dogs are DEA 4 positive. DEA 4 antibodies do not cause haemolysis and this group requires minimal consideration with regard to transfusions.

The DEA system is based on antigens which have currently been identified, but the possible existence of further antigens capable of producing an incompatibility reaction should always be considered. Once again, this indicates the importance of blood cross-matching any recipient who has had a previous transfusion, irrespective of whether the same donor is being used or the blood type of the donor and recipient are known.

Susan F Beck BVMS MRCVS

Cross Matching
Test Name: Blood Cross Match
Test Code: BCM
Sample : EDTA ± Serum from donor and recipient

Blood Typing
Test Name: Canine Blood Typing
Test Code: CBT
Sample : EDTA 

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CLIN PATH CLUB 
The Clin Path Club meetings are open to all veterinary surgeons and veterinary nurses.

Next Meeting: Thurs 12th September 2002 

Venue: Swallow Hotel, Samlesbury, Preston New Road, Preston. (Leave M6 J31, follow A59 signs to Blackburn, hotel just before 1st traffic lights)

Speaker: Dr Ian Ramsey BVSc PhD Dip ECVIM MRCVS: Recent advances in the diagnosis and treatment of Canine hyperadrenocorticism

Case book studies: If you would like to present an interesting case please contact Jane Miller on 01253 899215 or e-mail

To book your place, request further information or a location map call Joanne Kenyon on 01253 899215 or e-mail

IMPORTANT - This speaker is proving to be very popular. Due to a restriction on the number of bodies we can accommodate please make sure you reserve your place early. If you have to cancel we would appreciate a call.
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CLIN PATH CLUB - Dates for 2002 
Please make a note in your diary of the forthcoming meetings :- 

•  Thurs 14th November 2002 Dr A Coughlan BVSc Cert VA DSAS (Orth) PhD FRCVS Working up the lame dog "Tricks and Traps"

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HIllarious Histories

Interpreting Clin-Path results is always interesting, often fascinating and sometimes downright hilarious, particularly when it comes to case histories. Here are just a few examples, with “translation”, where appropriate:-

• · Showing mild paresis and four limb (fore-limb) ataxia.
• · He suffers from recurrent Sudomoanas infection.
• · The owner complains of gassy guts and dark motions.
• · Vomiting, straining and difficulty passing stones (stools).

• · Apologies for the small sample, getting it was not the most enjoyable experience.

“Following the BSE research mix up DEFRA is considering using only UKAS accredited laboratories in future”
Following the mix up at the Institute of Animal Health in Edinburgh between the ovine and bovine brain material used in a BSE research project DEFRA is considering using only UKAS accredited laboratories in future.
This decision has been prompted by a statement from the Chairman of the Food Standards Agency Sir John Krebs. He stated that a recent review of the FSA’s research portfolio and research management systems had identified the value of third party accreditation of research establishments. 

There has been a reluctance for research and academic establishments to seek accreditation to the new ISO 17025 standard, it had been considered too inflexible and inappropriate. It is UKAS’s opinion that the standard provides the criteria for accreditation but is not prescriptive. This allows sufficient flexibility in the application of the standard to meet the requirements of a particular laboratory.

NWL is accredited by UKAS to ISO 17025,  testing laboratory number 1733
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Tail End 
“Dogs are just People who wag their tails!"

Humanisation of dogs is exploding, from dog restaurants to canine massage parlours dogs are enjoying the pleasures once only available to humans.

It’s not just material comforts they are enjoying, 38% of Americans (40 million) call their answer machines to leave messages for their pets while they are out. Birthday parties for dogs are common and you can even buy edible birthday cards.

Psychologists are worried by such increasingly odd human behaviour. One American actress neutered her dog herself rather than trust the vet. “I was not going to let a stranger touch my Cyrus in that private spot with a knife” she said “I had the testicles embalmed and put them in a jar on my mantelpiece so Cyrus knows they are not far away”. (In case he should ever need them! sic).

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