Capillaria plica
Encyclopedia
Capillaria plica is a parasitic
nematode
which is most often found in the urinary bladder
, and occasionally in the kidneys, of dog
s and fox
es. It has also been found in the domestic cat
, and various wild mammal
s. Its presence usually produces no clinical symptoms, but in some cases, it leads to hematuria
(blood in the urine), cystitis
(inflammation of the urinary bladder), or difficulty in urination.
Males are 13–30 mm long and females are 30–60 mm long. Eggs are colorless, oval and pitted, and measure 50-68 µm by 22-32 µm.
or kidney
s of dog
s and cat
s in North America
, Europe
, Asia
and Africa
. It has also been identified in the urinary bladder and kidneys of several wild mammals in North America and Europe:
. First stage larvae (L1) develop within the eggshell in 30–36 days. When eaten by the intermediate host
-- earthworm
s of the genera Lumbricus
or Dendrobaena -- the L1 larvae hatch in the earthworm's intestine. The larvae burrow through the intestinal wall and become embedded in connective tissue
throughout the worm's body. If the earthworm is eaten by a suitable mammalian host, the larvae molt
into second stage larvae (L2), burrow through the intestinal wall, and molt again into third stage larvae (L3). The L3 are carried through the circulatory system
to the glomeruli
of the kidney
s. From there, they travel down the ureter
to the urinary bladder
. By 33 days post-infection, third (L3) and fourth-stage larvae (L4) are found in the urinary bladder. Here they mature into adults and reproduce sexually, shedding fertilized eggs into the urine of the host within about 60 days of infection. Detailed life cycle studies have not been carried out with wild animal definitive hosts.
(inflammation of the urinary bladder), mild proteinuria
(protein in the urine), and hematuria
(blood in the urine). Mild inflammation of the ureter has also been reported.
, ivermectin or fenbendazole
have been reported.
Parasitism
Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the other, the host. Traditionally parasite referred to organisms with lifestages that needed more than one host . These are now called macroparasites...
nematode
Nematode
The nematodes or roundworms are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic. It has been estimated that the total number of nematode...
which is most often found in the urinary bladder
Urinary bladder
The urinary bladder is the organ that collects urine excreted by the kidneys before disposal by urination. A hollow muscular, and distensible organ, the bladder sits on the pelvic floor...
, and occasionally in the kidneys, of dog
Dog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
s and fox
Fox
Fox is a common name for many species of omnivorous mammals belonging to the Canidae family. Foxes are small to medium-sized canids , characterized by possessing a long narrow snout, and a bushy tail .Members of about 37 species are referred to as foxes, of which only 12 species actually belong to...
es. It has also been found in the domestic cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
, and various wild mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s. Its presence usually produces no clinical symptoms, but in some cases, it leads to hematuria
Hematuria
In medicine, hematuria, or haematuria, is the presence of red blood cells in the urine. It may be idiopathic and/or benign, or it can be a sign that there is a kidney stone or a tumor in the urinary tract , ranging from trivial to lethal...
(blood in the urine), cystitis
Cystitis
Cystitis is a term that refers to urinary bladder inflammation that results from any one of a number of distinct syndromes. It is most commonly caused by a bacterial infection in which case it is referred to as a urinary tract infection.-Signs and symptoms:...
(inflammation of the urinary bladder), or difficulty in urination.
Taxonomy and Description
This species was originally described in 1819, and named Capillaria plica. In 1982, the suggestion was made that C. plica be transferred to the genus Pearsonema Freitas & Mendonça 1960, as Pearsonema plica. Currently, both names are used in the literature with roughly equal frequency. For example, searches of the PubMed database performed on 22 Nov 2008 yielded the same number of hits dated 2000 or later using either Capillaria plica or Pearsonema plica.Males are 13–30 mm long and females are 30–60 mm long. Eggs are colorless, oval and pitted, and measure 50-68 µm by 22-32 µm.
Hosts and distribution
Capillaria plica is often found in the urine, urinary bladderUrinary bladder
The urinary bladder is the organ that collects urine excreted by the kidneys before disposal by urination. A hollow muscular, and distensible organ, the bladder sits on the pelvic floor...
or kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
s of dog
Dog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
s and cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
and Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
. It has also been identified in the urinary bladder and kidneys of several wild mammals in North America and Europe:
- American BadgerAmerican BadgerThe American badger is a North American badger, somewhat similar in appearance to the European badger. It is found in the western and central United States, northern Mexico and central Canada, as well as in certain areas of southwestern British Columbia.Their habitat is typified by open...
(Taxidea taxus; North America) - American MinkAmerican MinkThe American mink is a semi-aquatic species of Mustelid native to North America, though human intervention has expanded its range to many parts of Europe and South America. Because of this, it is classed as Least Concern by the IUCN. Since the extinction of the sea mink, the American mink is the...
(Mustela vison; in introduced European populations) - Brown BearBrown BearThe brown bear is a large bear distributed across much of northern Eurasia and North America. It can weigh from and its largest subspecies, the Kodiak Bear, rivals the polar bear as the largest member of the bear family and as the largest land-based predator.There are several recognized...
(Ursus arctos; Russia) - CoyoteCoyoteThe coyote , also known as the American jackal or the prairie wolf, is a species of canine found throughout North and Central America, ranging from Panama in the south, north through Mexico, the United States and Canada...
(Canis latrans; North America) - European Badger (Meles meles; Europe)
- European minkEuropean minkThe European mink , also known as the Russian mink, is a semi-aquatic species of Mustelid native to Europe. It is listed by the IUCN as Endangered due to an ongoing reduction in numbers, having been calculated as being more than 50% over the past three generations...
(Mustela lutreola; Europe) - FisherFisher (animal)The fisher is a medium-size mammal native to North America. It is a member of the mustelid family, commonly referred to as the weasel family. The fisher is closely related to but larger than the American Marten...
(Martes pennanti; North America) - LynxLynxA lynx is any of the four Lynx genus species of medium-sized wildcats. The name "lynx" originated in Middle English via Latin from Greek word "λύγξ", derived from the Indo-European root "*leuk-", meaning "light, brightness", in reference to the luminescence of its reflective eyes...
(Felis lynx; Lithuania) - MartenMartenThe martens constitute the genus Martes within the subfamily Mustelinae, in family Mustelidae.-Description:Martens are slender, agile animals, adapted to living in taigas, and are found in coniferous and northern deciduous forests across the northern hemisphere. They have bushy tails, and large...
(Martes americanus; North America) - Masked Shrew (Sorex cinereus; North America)
- Northern Short-tailed ShrewNorthern Short-tailed ShrewThe Northern Short-tailed Shrew is the largest shrew in the genus Blarina, and occurs in the northeastern region of North America. It is a semifossorial, highly active and voracious insectivore and is present in a variety of habitats. It is notable in that it is one of the few venomous mammals...
(Blarina brevicauda; North America) - RaccoonRaccoonProcyon is a genus of nocturnal mammals, comprising three species commonly known as raccoons, in the family Procyonidae. The most familiar species, the common raccoon , is often known simply as "the" raccoon, as the two other raccoon species in the genus are native only to the tropics and are...
(Procyon lotor; North America) - Raccoon DogRaccoon DogThe raccoon dog , also known as the magnut or tanuki, is a canid indigenous to east Asia. It is the only extant species in the genus Nyctereutes...
(Nyctereutes procyonoides; Europe) - Red FoxRed FoxThe red fox is the largest of the true foxes, as well as being the most geographically spread member of the Carnivora, being distributed across the entire northern hemisphere from the Arctic Circle to North Africa, Central America, and the steppes of Asia...
(Vulpes vulpes; North America and Europe) - SkunkSkunkSkunks are mammals best known for their ability to secrete a liquid with a strong, foul odor. General appearance varies from species to species, from black-and-white to brown or cream colored. Skunks belong to the family Mephitidae and to the order Carnivora...
(Mephitis mephitis; North America) - Wolf (Canis lupus; Europe)
Life cycle
In dogs and cats, eggs of Capillaria plica are released in the urine of the mammalian definitive hostParasitic life cycles
Parasite life cycles can take a variety of forms, all involving the exploitation of one or more hosts. Those that must infect more than one host species to complete their life cycles are said to have complex or indirect life cycles, while those that infect a single species have direct life...
. First stage larvae (L1) develop within the eggshell in 30–36 days. When eaten by the intermediate host
Parasitic life cycles
Parasite life cycles can take a variety of forms, all involving the exploitation of one or more hosts. Those that must infect more than one host species to complete their life cycles are said to have complex or indirect life cycles, while those that infect a single species have direct life...
-- earthworm
Earthworm
Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...
s of the genera Lumbricus
Lumbricus
Lumbricus contains some of the most commonly seen earthworms in Europe. The genus has nearly 700 valid species.Characteristics of some commonly encountered species are:...
or Dendrobaena -- the L1 larvae hatch in the earthworm's intestine. The larvae burrow through the intestinal wall and become embedded in connective tissue
Connective tissue
"Connective tissue" is a fibrous tissue. It is one of the four traditional classes of tissues . Connective Tissue is found throughout the body.In fact the whole framework of the skeleton and the different specialized connective tissues from the crown of the head to the toes determine the form of...
throughout the worm's body. If the earthworm is eaten by a suitable mammalian host, the larvae molt
Moult
In biology, moulting or molting , also known as sloughing, shedding, or for some species, ecdysis, is the manner in which an animal routinely casts off a part of its body , either at specific times of year, or at specific points in its life cycle.Moulting can involve the epidermis , pelage...
into second stage larvae (L2), burrow through the intestinal wall, and molt again into third stage larvae (L3). The L3 are carried through the circulatory system
Circulatory system
The circulatory system is an organ system that passes nutrients , gases, hormones, blood cells, etc...
to the glomeruli
Glomerulus
A glomerulus is a capillary tuft that is involved in the first step of filtering blood to form urine.A glomerulus is surrounded by Bowman's capsule, the beginning component of nephrons in the vertebrate kidney. A glomerulus receives its blood supply from an afferent arteriole of the renal...
of the kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
s. From there, they travel down the ureter
Ureter
In human anatomy, the ureters are muscular tubes that propel urine from the kidneys to the urinary bladder. In the adult, the ureters are usually long and ~3-4 mm in diameter....
to the urinary bladder
Urinary bladder
The urinary bladder is the organ that collects urine excreted by the kidneys before disposal by urination. A hollow muscular, and distensible organ, the bladder sits on the pelvic floor...
. By 33 days post-infection, third (L3) and fourth-stage larvae (L4) are found in the urinary bladder. Here they mature into adults and reproduce sexually, shedding fertilized eggs into the urine of the host within about 60 days of infection. Detailed life cycle studies have not been carried out with wild animal definitive hosts.
Prevalence
Prevalence rates of up to 50% in wild hosts and 76% in kennel dogs have been reported.Clinical symptoms
Most infected animals exhibit no clinical symptoms. In cases of heavy infestation, symptoms may include cystitisCystitis
Cystitis is a term that refers to urinary bladder inflammation that results from any one of a number of distinct syndromes. It is most commonly caused by a bacterial infection in which case it is referred to as a urinary tract infection.-Signs and symptoms:...
(inflammation of the urinary bladder), mild proteinuria
Proteinuria
Proteinuria means the presence of anexcess of serum proteins in the urine. The protein in the urine often causes the urine to become foamy, although foamy urine may also be caused by bilirubin in the urine , retrograde ejaculation, pneumaturia due to a fistula, or drugs such as pyridium.- Causes...
(protein in the urine), and hematuria
Hematuria
In medicine, hematuria, or haematuria, is the presence of red blood cells in the urine. It may be idiopathic and/or benign, or it can be a sign that there is a kidney stone or a tumor in the urinary tract , ranging from trivial to lethal...
(blood in the urine). Mild inflammation of the ureter has also been reported.
Diagnosis and treatment
Diagnosis in cases of hematuria or cystitis is made by finding eggs in the urine sediment. Successful treatment with levamisoleLevamisole
Levamisole is an anthelminthic and immunomodulator belonging to a class of synthetic imidazothiazole derivatives. It was discovered at Janssen Pharmaceutica in 1966...
, ivermectin or fenbendazole
Fenbendazole
Fenbendazole is a broad spectrum benzimidazole anthelmintic used against gastrointestinal parasites including roundworms, hookworms, whipworms, the taenia species of tapeworms, pinworms, aelurostrongylus, paragonimiasis, strongyles and strongyloides and can be administered to sheep, cattle,...
have been reported.