parasites


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Related to parasites: Protozoa, Parasitic diseases

par·a·sites

parasitophobia.

splenomegaly

Enlarged spleen Enlargement of spleen for any reason, which is usually a manifestation of underlying disease; the only specific finding in splenomegaly is dragging sensation in the upper right quadrant; megalic spleens may reach 4.0+ kg–eg, in agnogenic myeloid metaplasia
Splenomegaly
Congestion Cirrhosis, CHF, thrombosis of portal or splenic veins
Infection
• Bacteria Brucellosis, infective carditis agents, syphilis, TB, typhoid fever
• Fungi Histoplasmosis
• Parasites Echinococcosis, leishmaniasis, malaria, schistosomiasis, toxoplasmosis, trypanosomiasis
• Viruses CMV, EBV
Inflammatory/immune-related Rheumatoid arthritis, SLE
Hematopoietic disease/Lymphoid function
• Malignant Leukemias, eg ALL, CLL, myeloproliferative disorders–eg agnogenic myeloid metaplasia, CML, multiple myeloma, polycythemia vera; lymphomas–Hodgkin's disease, NHL
• Nonmalignant Hemolytic anemia, histiocytosis, ITP
Storage diseases Gaucher's disease, mucopolysaccharidosis, Niemann-Pick disease
Etc Amyloidosis, cysts, hypersplenism, metastases, primary tumors

transfusion reaction

Blood transfusion reaction, incompatibility reaction Transfusion medicine Any untoward response to the transfusion of non-self blood products, in particular RBCs, which evokes febrile reactions that are either minor–occurring in 1:40 transfusions and attributed to nonspecific leukocyte-derived pyrogens, or major–occurring in 1:3000 transfusions and caused by a true immune reaction, which is graded according to the presence of urticaria, itching, chills, fever and, if the reaction is intense, collapse, cyanosis, chest and/or back pain and diffuse hemorrhage Note: If any of above signs appear in a transfusion reaction, or if the temperature rises 1ºC, the transfusion must be stopped; most Pts survive if < 200 ml has been transfused in cases of red cell incompatibility-induced transfusion reaction; over 50% die when 500 ml or more has been transfused; TF mortality is ± 1.13/105 transfusions Clinical Flank pain, fever, chills, bloody urine, rash, hypotension, vertigo, fainting
Transfusion reactions
Immune, non-infectious transfusion reactions  
• Allergic Urticaria with immediate hypersensitivity
• Anaphylaxis Spontaneous anti-IgA antibody formation, occurs in ± 1:30 of Pts with immunoglobulin A deficiency, which affects 1:600 of the general population–total frequency: 1/30 X 1/600 = 1/18,000
• Antibodies to red cell antigens, eg antibodies to ABH, Ii, MNSs, P1, HLA
• Serum sickness Antibodies to donor's immunoglobulins and proteins
Non-immune, non-infectious transfusion reactions  
• Air embolism A problem of historic interest that occurred when air vents were included in transfusion sets
• Anticoagulant Citrate anticoagulant may cause tremors and EKG changes
• Coagulation defects Depletion of factors VIII and V; this 'dilutional' effect requires massive transfusion of 10 + units before becoming significant
• Cold blood In ultra-emergent situations, blood stored at 4º C may be tranfused prior to reaching body temperature at 37º C; warming a unit of blood from 4 to 37º C requires 30 kcal/L of energy, consumed as glucose; cold blood slows metabolism, exacerbates lactic acidosis, ↓ available calcium, ↑ hemoglobin's affinity for O2 and causes K+ leakage, a major concern in cold hemoglobinuria
• Hemolysis A phenomenon due to blood collection trauma, a clinically insignificant problem
• Hyperammonemia and lactic acid Both molecules accumulate during packed red cell storage and when transfused, require hepatorenal clearance, of concern in Pts with hepatic or renal dysfunction, who should receive the freshest units possible
• Hyperkalemia Hemolysis causes an ↑ of 1 mmol/L/day of potassium in a unit of stored blood, of concern in Pts with poor renal function, potentially causing arrhythmia
• Iron overload Each unit of packed RBCs has 250 mg iron, potentially causing hemosiderosis in multi-transfused Pts
Microaggregates Sludged debris in the pulmonary vasculature causing ARDS may be removed with micropore filters
Pseudoreaction Transfusion reaction mimics, eg anxiety, anaphylaxis related to a drug being administered at the same time as the transfusion
Infections transmitted by blood transfusion
• Viruses B19, CMV, EBV, HAV, HBV, HCV, HDV, HEV, Creutzfeldt-Jakob disease, Colorado tick fever, tropical viruses–eg Rift Valley fever, Ebola, Lassa, dengue, HHV 6, HIV-1, HIV-2, HTLV-I, HTLV-II
• Bacteria Transmission of bacterial infections from an infected donor is uncommon and includes brucellosis and syphilis in older reports; more recent reports include Lyme disease and Yersinia enterocolitica  Note: Although virtually any bacteria could in theory be transmitted in blood, the usual cause is contamination during processing rather than transmission from an infected donor
• Parasites Babesiosis, Leishmania donovani, L tropica, malaria, microfilariasis–Brugia malayi, Loa loa, Mansonella perstans, Mansonella ozzardi, Toxoplasma gondii, Trypanosoma cruzi
References in periodicals archive ?
The first option is to select individual animals with possible genetic resistance to parasites. Generally, animals that are healthy, productive, have good body condition, and tend to maintain a low parasite load without deworming are often going to be the ones to select to not deworm.
Only female mosquitoes spread the malaria parasites. When a mosquito bites a person who already has malaria, it sucks up the person's blood, which contain the parasites.
To analyze the ancient parasite's DNA, the team rehydrated the coprolite to retrieve the parasite's eggs, after which they then proceeded to isolate the DNA from them.
'Even though thousands of parasites invade the salivary gland, less than a 10th of them are transmitted during a mosquito bite,' says Michael Wells, Ph.D., postdoctoral researcher in Andrew's laboratory and the study's lead author.
Mosquitoes are required to transmit malaria, acquiring malaria parasites by biting an infected person, then transmitting the disease weeks later after the parasite has completed development in the mosquito.
However, the adult parasites often reside in the gut of the definitive host, absorbing nutrients that the host consumes.
When plankton parasites infect and kill their host, they rob higher order species like krill of a potential source of nutrition.
'We found that platelets may kill around 20 per cent of circulating Plasmodium parasites in clinical malaria, and in P.
"I spent more than 20 years of experience as a surgeon, but I have not found parasites this big in the intestines of South Koreans," said the head of the soldier's medical team, Lee Cook-jong, in a press conference.
Enolva said that aside from parasites, stranded dolphins were also observed to had been infected with sea lice, found in their eyes.
Read on to meet four mind-controlling parasites and their zombie hosts--if you dare!
The natural world is full of examples where parasites are harmful under some conditions and helpful under others.