Pug Health Information
Pug Dog Encephalitis (PDE/NME)
Pug dog encephalitis (PDE) is a severe and debilitating disease in Pugs that causes inflammation of the brain. This condition is inherited in Pugs but can occur in other breeds as well.
Unfortunately, the disease is fatal and it is estimated that 1.2% of Pugs will die from Pug encephalitis. Although there is no cure for this disease, early diagnosis and management can help your dog maintain a good quality of life for as long as possible.
What is Pug Dog Encephalitis?
Pug dog encephalitis is the colloquial name for Necrotizing Meningoencephalitis (NME), a severe and incurable condition that causes inflammation and death of the brain tissue.
Although the disease primarily affects Pugs, other small breed dogs—including Maltese, Chihuahuas, and Yorkshire Terriers, can be affected as well.
Young adults are most commonly affected, with most being diagnosed before seven years of age. Young, fawn-colored, female Pugs are especially prone to developing this condition.
What Causes the Condition?
Pug encephalitis is believed to be an inherited autoimmune disorder. In Pugs, genetic markers have been identified that can predict a dog’s risk for developing the disease. One in eight Pugs with two copies of these genetic markers will develop Pug encephalitis in their lifetime. At this time, it is not known why some dogs develop the disease while others do not.
Symptoms of Pug Dog Encephalitis
The symptoms of Pug dog encephalitis may come on gradually or may progress rapidly depending on the patient. Many cases start with vague symptoms such as lethargy and depression, which can often be overlooked.
As the disease progresses, pet owners may notice more dramatic symptoms, such as:
Pug dog encephalitis (PDE) is a severe and debilitating disease in Pugs that causes inflammation of the brain. This condition is inherited in Pugs but can occur in other breeds as well.
Unfortunately, the disease is fatal and it is estimated that 1.2% of Pugs will die from Pug encephalitis. Although there is no cure for this disease, early diagnosis and management can help your dog maintain a good quality of life for as long as possible.
What is Pug Dog Encephalitis?
Pug dog encephalitis is the colloquial name for Necrotizing Meningoencephalitis (NME), a severe and incurable condition that causes inflammation and death of the brain tissue.
Although the disease primarily affects Pugs, other small breed dogs—including Maltese, Chihuahuas, and Yorkshire Terriers, can be affected as well.
Young adults are most commonly affected, with most being diagnosed before seven years of age. Young, fawn-colored, female Pugs are especially prone to developing this condition.
What Causes the Condition?
Pug encephalitis is believed to be an inherited autoimmune disorder. In Pugs, genetic markers have been identified that can predict a dog’s risk for developing the disease. One in eight Pugs with two copies of these genetic markers will develop Pug encephalitis in their lifetime. At this time, it is not known why some dogs develop the disease while others do not.
Symptoms of Pug Dog Encephalitis
The symptoms of Pug dog encephalitis may come on gradually or may progress rapidly depending on the patient. Many cases start with vague symptoms such as lethargy and depression, which can often be overlooked.
As the disease progresses, pet owners may notice more dramatic symptoms, such as:
- Seizures
- Collapse
- Circling
- Head Pressing
- Appearing lost or disoriented
- Behavior changes
- Weakness, stumbling
- Blindness
- Abnormal gait
- Coma
- Dogs with N/N haplotype have no copies of the NME-associated risk variants and are at low risk of developing necrotizing meningoencephalitis. They cannot transmit these NME risk variants to their offspring.
- Dogs with N/S haplotype have one copy of the NME-associated risk variants and are at low risk of developing necrotizing meningoencephalitis. They may transmit these NME risk variants to 50% of their offspring.
- Dogs with S/S haplotype have two copies of the NME-associated risk variants and are 12.75 times more likely to develop necrotizing meningoencephalitis in their lifetimes. They will transmit these NME risk variants to all of their offspring.
May-Hegglin Anomaly Pug Dog Type (MHA)
May-Hegglin Anomaly Pug Dog type (MHA) is a hereditary blood disorder reported until now only in Pug dog breed. May-Hegglin anomaly belongs in group of disorders known as thrombocytopenia, a medical condition characterized by low blood platelet count in affected animals. Except in pugs, May Hegglin anomaly is affecting also human beings. It is named after German physician Richard May, and Swiss physician Robert Hegglin.
Platelets, or thrombocytes, have a key role in bleeding prevention through clumping of blood vessel injuries. Platelets are produced in the bone marrow and then released into the blood stream. At a site of vascular injury, platelets are exposed to surface which is not from blood vessel, and they initiate to aggregate to each other, which results in formation of a hemostatic plug that will seal the defect.
Characteristics and symptoms
In May-Hegglin anomaly affected pugs, platelets appear to be bigger and their count lower than normal. Changes in neutrophils have been observed as well. The disorder may cause prolonged bleeding time and bruising, which can cause problems post operation. Other than that, no additional clinical signs are usually observed. In human patients, renal disease, hearing problems and cataracts are common, but these symptoms have not been reported in Pugs. Usually, May Hegglin anomaly requires no treatment, except in extreme cases when platelet transfusions may be necessary.
Genetics
May-Hegglin anomaly pug type (MHA) is caused by mutation of MYH9 gene. The disorder is inherited as an autosomal dominant trait. It is needed one copy of the mutated gene for dog to develop symptoms. When mating healthy, unaffected dog with a heterozygous affected dog, chances are 50% that the cub will be affected as well. The disorder equally affects both female and male dogs.
May-Hegglin Anomaly Pug Dog type (MHA) is a hereditary blood disorder reported until now only in Pug dog breed. May-Hegglin anomaly belongs in group of disorders known as thrombocytopenia, a medical condition characterized by low blood platelet count in affected animals. Except in pugs, May Hegglin anomaly is affecting also human beings. It is named after German physician Richard May, and Swiss physician Robert Hegglin.
Platelets, or thrombocytes, have a key role in bleeding prevention through clumping of blood vessel injuries. Platelets are produced in the bone marrow and then released into the blood stream. At a site of vascular injury, platelets are exposed to surface which is not from blood vessel, and they initiate to aggregate to each other, which results in formation of a hemostatic plug that will seal the defect.
Characteristics and symptoms
In May-Hegglin anomaly affected pugs, platelets appear to be bigger and their count lower than normal. Changes in neutrophils have been observed as well. The disorder may cause prolonged bleeding time and bruising, which can cause problems post operation. Other than that, no additional clinical signs are usually observed. In human patients, renal disease, hearing problems and cataracts are common, but these symptoms have not been reported in Pugs. Usually, May Hegglin anomaly requires no treatment, except in extreme cases when platelet transfusions may be necessary.
Genetics
May-Hegglin anomaly pug type (MHA) is caused by mutation of MYH9 gene. The disorder is inherited as an autosomal dominant trait. It is needed one copy of the mutated gene for dog to develop symptoms. When mating healthy, unaffected dog with a heterozygous affected dog, chances are 50% that the cub will be affected as well. The disorder equally affects both female and male dogs.
Pyruvate kinase deficiency of erythrocytes, PK deficiency
Pyruvate kinase deficiency (PKDef) is an inherited hemolytic anemia caused by a defect in the enzyme pyruvate kinase.
Deficiency of this enzyme results primarily in easily damaged red blood cells (hemolysis). Affected dogs typically present between 4 months and 2 year of age with pale gums from decreased numbers of red blood cells (Anemia) and lethargy or exercise intolerance. Clinical findings during a veterinary exam include severe anemia, hardening of the bones, and an enlarged spleen and liver. While dogs can live for several years with this disease, they typically die from severe anemia or liver failure between 5 to 9 years of age.
Explanation of Results:
Pyruvate kinase deficiency (PKDef) is an inherited hemolytic anemia caused by a defect in the enzyme pyruvate kinase.
Deficiency of this enzyme results primarily in easily damaged red blood cells (hemolysis). Affected dogs typically present between 4 months and 2 year of age with pale gums from decreased numbers of red blood cells (Anemia) and lethargy or exercise intolerance. Clinical findings during a veterinary exam include severe anemia, hardening of the bones, and an enlarged spleen and liver. While dogs can live for several years with this disease, they typically die from severe anemia or liver failure between 5 to 9 years of age.
Explanation of Results:
- Dogs with N/N genotype will not have pyruvate kinase deficiency and cannot transmit this variant to their offspring.
- Dogs with N/K genotype are not expected to show signs of pyruvate kinase deficiency but have half the normal level of pyruvate kinase activity, and are carriers. They may transmit this variant to 50% of their offspring. Matings between two carriers are predicted to produce 25% pyruvate kinase deficiency-affected puppies.
- Dogs with K/K genotype will have pyruvate kinase deficiency.
Hyperuricosuria (HUU)
Hyperuricosuria is an inherited disorder characterized by elevated levels of uric acid in the urine that can lead to the formation of bladder/kidney stones.
Hyperuricosuria (HUU) means elevated levels of uric acid in the urine. This trait predisposes dogs to form stones in their bladders or sometimes kidneys. These stones often must be removed surgically and can be difficult to treat. HUU is inherited as a simple autosomal recessive defect. A mutation in exon 5 of the gene Solute carrier family 2, member 9 (SLC2A9) has been found to be associated with hyperuricosuria in dogs. HUU can occur in any breed but is most commonly found in the Dalmatian, Bulldog, and Black Russian Terrier.
A DNA test for the SLC2A9 mutation can determine the genetic status of dogs for HUU. Dogs that carry two copies of the mutation will be affected and susceptible to develop bladder/kidney stones. However, the SCL2A9 mutation is not the sole cause of urate bladder stones in dogs. Other factors, in addition to genetic test results, such as liver disease and diet need also be considered in clinical evaluation.
Explanation of Results:
Hyperuricosuria is an inherited disorder characterized by elevated levels of uric acid in the urine that can lead to the formation of bladder/kidney stones.
Hyperuricosuria (HUU) means elevated levels of uric acid in the urine. This trait predisposes dogs to form stones in their bladders or sometimes kidneys. These stones often must be removed surgically and can be difficult to treat. HUU is inherited as a simple autosomal recessive defect. A mutation in exon 5 of the gene Solute carrier family 2, member 9 (SLC2A9) has been found to be associated with hyperuricosuria in dogs. HUU can occur in any breed but is most commonly found in the Dalmatian, Bulldog, and Black Russian Terrier.
A DNA test for the SLC2A9 mutation can determine the genetic status of dogs for HUU. Dogs that carry two copies of the mutation will be affected and susceptible to develop bladder/kidney stones. However, the SCL2A9 mutation is not the sole cause of urate bladder stones in dogs. Other factors, in addition to genetic test results, such as liver disease and diet need also be considered in clinical evaluation.
Explanation of Results:
- Dogs with N/N genotype will not have hyperuricosuria and will not transmit this hyperuricosuria variant to their offspring.
- Dogs with N/HU genotype will not have hyperuricosuria, but are carriers. They will transmit this variant to 50% of their offspring. Matings between two carriers are predicted to produce 25% hyperuricosuria-affected puppies.
- Dogs with HU/HU genotype will be affected and are susceptible to develop bladder/kidney stones. They will transmit this hyperuricosuria variant to all of their offspring.
