''Capillaria plica'' (dog bladder worm) is a

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The ent ...

nematode The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (h ...

which is most often found in the

urinary bladder The bladder () is a hollow organ in humans and other vertebrates that stores urine from the Kidney (vertebrates), kidneys. In placental mammals, urine enters the bladder via the ureters and exits via the urethra during urination. In humans, the ...

, and occasionally in the

kidney In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organ (anatomy), organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and rig ...

s, of

dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the gray wolf. Also called the domestic dog, it was selectively bred from a population of wolves during the Late Pleistocene by hunter-gatherers. ...

s and

fox Foxes are small-to-medium-sized omnivorous mammals belonging to several genera of the family Canidae. They have a flattened skull; upright, triangular ears; a pointed, slightly upturned snout; and a long, bushy tail ("brush"). Twelve species ...

es. It has also been found in the domestic

cat The cat (''Felis catus''), also referred to as the domestic cat or house cat, is a small domesticated carnivorous mammal. It is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the ...

, and various wild

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

s. Its presence usually produces no clinical symptoms, but in some cases, it leads to

hematuria Hematuria or haematuria is defined as the presence of blood or red blood cells in the urine. "Gross hematuria" occurs when urine appears red, brown, or tea-colored due to the presence of blood. Hematuria may also be subtle and only detectable with ...

(blood in the urine),

cystitis A urinary tract infection (UTI) is an infection that affects a part of the urinary tract. Lower urinary tract infections may involve the bladder (cystitis) or urethra ( urethritis) while upper urinary tract infections affect the kidney (py ...

(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 th
PubMed
database performed on 22 Nov 2008 yielded the same number of hits dated 2000 or later using either ''Capillaria plica'' or ''Pearsonema plica''.

Hosts and distribution

''Capillaria plica'' is often found in the urine,

s of

s and

s in

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

and

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

. It has also been identified in the urinary bladder and kidneys of several wild mammals in North America and Europe: * American badger (''Taxidea taxus''; North America) *

American mink The American mink (''Neogale vison'') is a semiaquatic species of Mustelidae, mustelid native to North America, though human introduction has expanded its range to many parts of Europe, Asia, and South America. Because of range expansion, the Am ...

(''Mustela vison''; in introduced European populations) *

Brown bear The brown bear (''Ursus arctos'') is a large bear native to Eurasia and North America. Of the land carnivorans, it is rivaled in size only by its closest relative, the polar bear, which is much less variable in size and slightly bigger on av ...

(''Ursus arctos''; Russia) *

Coyote The coyote (''Canis latrans''), also known as the American jackal, prairie wolf, or brush wolf, is a species of canis, canine native to North America. It is smaller than its close relative, the Wolf, gray wolf, and slightly smaller than the c ...

(''Canis latrans''; North America) *

European badger The European badger (''Meles meles''), also known as the Eurasian badger, is a badger species in the family Mustelidae native to Europe and West Asia and parts of Central Asia. It is classified as least concern on the IUCN Red List, as it has a w ...

(''Meles meles''; Europe) *

European mink The European mink (''Mustela lutreola''), also known as the Russian mink and Eurasian mink, is a semiaquatic species of mustelid native to Europe. It is similar in colour to the American mink, but is slightly smaller and has a less specialize ...

(''Mustela lutreola''; Europe) * Fisher (''Martes pennanti''; North America) *

Lynx A lynx ( ; : lynx or lynxes) is any of the four wikt:extant, extant species (the Canada lynx, Iberian lynx, Eurasian lynx and the bobcat) within the medium-sized wild Felidae, cat genus ''Lynx''. The name originated in Middle Engl ...

(''Felis lynx''; Lithuania) *

Marten A marten is a weasel-like mammal in the genus ''Martes'' within the subfamily Guloninae, in the family Mustelidae. They have bushy tails and large paws with partially retractile claws. The fur varies from yellowish to dark brown, depending on ...

(''Martes americanus''; North America) * Masked shrew (''Sorex cinereus''; North America) *

Northern short-tailed shrew The northern short-tailed shrew (''Blarina brevicauda'') 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 ...

(''Blarina brevicauda''; North America) *

Raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the North American, northern or common raccoon (also spelled racoon) to distinguish it from Procyonina, other species of raccoon, is a mammal native to North America. It is the largest ...

(''Procyon lotor''; North America) *

Raccoon dog ''Nyctereutes'' (Greek: ''nyx, nykt-'' "night" + ''ereutēs'' "wanderer") is a genus of canid which includes only two extant species, both known as raccoon dogs: the common raccoon dog (''Nyctereutes procyonoides'') and the Japanese raccoon do ...

(''Nyctereutes procyonoides''; Europe) *

Red fox The red fox (''Vulpes vulpes'') is the largest of the true foxes and one of the most widely distributed members of the order Carnivora, being present across the entire Northern Hemisphere including most of North America, Europe and Asia, plus ...

(''Vulpes vulpes''; North America and Europe) *

Skunk Skunks are mammals in the family Mephitidae. They are known for their ability to spray a liquid with a strong, unpleasant scent from their anal glands. Different species of skunk vary in appearance from black-and-white to brown, cream or gi ...

(''Mephitis mephitis''; North America) *

Wolf The wolf (''Canis lupus''; : wolves), also known as the grey wolf or gray wolf, is a Canis, canine native to Eurasia and North America. More than thirty subspecies of Canis lupus, subspecies of ''Canis lupus'' have been recognized, includin ...

(''Canis lupus''; Europe)

Life cycle

In dogs and cats, eggs of ''Capillaria plica'' are released in the urine of the mammalian

definitive host In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasitic, a mutualistic, or a commensalist ''guest'' (symbiont). The guest is typically provided with nourishment and shelter. Examples include ...

. First stage larvae (L1) develop within the eggshell in 30–36 days. When eaten by the

intermediate host In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasitic, a mutualistic, or a commensalist ''guest'' (symbiont). The guest is typically provided with nourishment and shelter. Examples include ...

earthworm An earthworm is a soil-dwelling terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the class (or subclass, depending on the author) Oligochaeta. In classical systems, they we ...

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 Connective tissue is one of the four primary types of animal tissue, a group of cells that are similar in structure, along with epithelial tissue, muscle tissue, and nervous tissue. It develops mostly from the mesenchyme, derived from the mesod ...

throughout the worm's body. If the earthworm is eaten by a suitable mammalian host, the larvae

molt In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is a process by which an animal casts off parts of its body to serve some beneficial purpose, either at ...

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 In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart ...

to the glomeruli of the

s. From there, they travel down the

ureter The ureters are tubes composed of smooth muscle that transport urine from the kidneys to the urinary bladder. In an adult human, the ureters typically measure 20 to 30 centimeters in length and about 3 to 4 millimeters in diameter. They are lin ...

to the

. 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.Olsen, O.W. (1974) "''Capillaria plica'' (Rudolphi, 1819)". In: ''Animal Parasites: Their Life Cycles and Ecology''. Third Edition. Dover: New York. , pp. 506-507. 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

(inflammation of the urinary bladder), mild

proteinuria Proteinuria is the presence of excess proteins in the urine. In healthy persons, urine contains very little protein, less than 150 mg/day; an excess is suggestive of illness. Excess protein in the urine often causes the urine to become fo ...

(protein in the urine), and

(blood in the urine). Mild inflammation of the ureter has also been reported.(PDF)
/ref>

Diagnosis and treatment

Diagnosis in cases of hematuria or cystitis is made by finding eggs in the urine sediment. Successful treatment with

levamisole Levamisole, sold under the brand name Ergamisol among others, is a medication used to treat parasitic worm infections, specifically ascariasis and hookworm infections. It is taken by mouth. Side effects may include abdominal pain, vomiting, ...

ivermectin Ivermectin is an antiparasitic drug. After its discovery in 1975, its first uses were in veterinary medicine to prevent and treat heartworm and acariasis. Approved for human use in 1987, it is used to treat infestations including head lice ...

fenbendazole Fenbendazole is a broad-spectrum benzimidazole anthelmintic used against gastrointestinal parasites including: roundworms, hookworms, whipworms, the tapeworm genus '' Taenia'' (but not effective against '' Dipylidium caninum'', a common dog ...

has been reported.

References

External links

''Capillaria plica'' infection. Merck Veterinary Manual
{{Taxonbar, from=Q144602 Parasites of cats Parasites of dogs Enoplia Parasitic nematodes of mammals Veterinary helminthology Nematodes described in 1819 Taxa named by Karl Rudolphi