Pneumonia in immunocompromised persons
Available online at http: Alternatively, a total dose infusion can be provided at one time. Use of the system assures reasonable comparisons by different observers and in different regions. Van Gossum q P. It has therefore been proposed that heme oxygenase, which produces CO, has a regulatory role in addition to its metabolic one. A beta-hemolytic streptococcus infection following a streptococcal infection of the throat or skin.
Major diseases of the respiratory system
A lack of vitamin C can result in scurvy. Scurvy is rare in industrialized nations, but it can affect older people, those who consume excessive quantities of alcohol, and people who do not eat fresh fruits and vegetables. Some infants and children who follow a limited diet for any reason may be prone to scurvy. According to the World Health Organization WHO , million people worldwide are malnourished, and stunted development due to poor diet affects million children globally. Malnutrition during childhood can lead not only to long-term health problems but also to educational challenges and limited work opportunities in the future.
Malnourished children often have smaller babies when they grow up. It can also slow recovery from wounds and illnesses, and it can complicate diseases such as measles , pneumonia , malaria , and diarrhea.
It can leave the body more susceptible to disease. Signs and symptoms of undernutrition include:. Eventually, there may be respiratory failure and heart failure , and the person may become unresponsive. Total starvation can be fatal within 8 to 12 weeks.
Children may show a lack of growth, and they may be tired and irritable. Behavioral and intellectual development may be slow, possibly resulting in learning difficulties. Even with treatment, there can be long-term effects on mental function, and digestive problems may persist. In some cases, these may be lifelong. Adults with severe undernourishment that started during adulthood usually make a full recovery with treatment. This may be caused by symptoms of an illness, for example, dysphagia , when it is difficult to swallow.
Badly fitting dentures may contribute. Conditions such as depression, dementia , schizophrenia , anorexia nervosa , and bulimia can lead to malnutrition. Some people cannot leave the house to buy food or find it physically difficult to prepare meals. Those who live alone and are isolated are more at risk.
Some people do not have enough money to spend on food, and others have limited cooking skills. If the body does not absorb nutrients efficiently, even a healthful diet may not prevent malnutrition. People with Crohn's disease or ulcerative colitis may need to have part of the small intestine removed to enable them to absorb nutrients.
Celiac disease is a genetic disorder that involves a gluten intolerance. It may result in damage to the lining of the intestines and poor food absorption. Addiction to alcohol can lead to gastritis or damage to the pancreas. These can make it hard to digest food, absorb certain vitamins, and produce hormones that regulate metabolism. Alcohol contains calories , so the person may not feel hungry. They may not eat enough proper food to supply the body with essential nutrients.
Not breastfeeding, especially in the developing world, can lead to malnutrition in infants and children. In some parts of the world, widespread and long-term malnutrition can result from a lack of food. There are several ways to identify adults who are malnourished or at risk of malnutrition, for example, the Malnutrition Universal Screening Tool MUST tool.
MUST has been designed to identify adults, and especially older people, with malnourishment or a high risk of malnutrition. If the person is at low risk of malnutrition, their overall score will be 0. Some complications are considerably more common in malnourished patients and those with inadequate nutrient intake than in well-nourished individuals. A longer recovery period.
Impaired host defenses and sepsis. Impaired GI tract function. Delayed bone callus formation. Section 1 - Malnutrition This page was last modified on August 11 RxKinetics, Plattsburg, MO A substance is added to the sample to activate the platelets and cause them to aggregate. The number of platelets is measured again — only those that have not aggregated will be counted the second time.
The difference between the first measurement and the second measurement is an indication of platelet function. Platelet aggregometry Many different substances can activate a platelet, including proteins in the wound, factors released from other activated platelets, and factors produced by the coagulation system that aids platelets in forming a strong plug to stop bleeding.
Many different platelet abnormalities have been described due to problems with one or more of these activating systems. Platelet aggregometry consists of 4 to 8 separate tests. In each test, a different platelet activating substance agonist is added to blood, followed by measurement of platelet aggregation over several minutes. When complete, the entire panel of tests is reviewed and interpreted to determine if there is any evidence of abnormal platelet function.
Platelet aggregation testing is the gold standard in platelet function testing and can diagnose a variety of inherited and acquired platelet function disorders. It is typically performed at academic medical centers or large hospitals due to the complexity of the testing and interpretation.
Lumiaggregometry Similar to platelet aggregometry, lumiaggregometry simultaneously measures the release of certain organic agents from platelet granules little sacs within the platelet utilizing a luminescence technique.
This technique measures the amount of light emitted when activating substances are added, that results in the conversion of ADP adenosine diphosphate to ATP adenosine triphosphate. This measurement reflects any abnormalities that may be present in platelet granules, a problem with patients with 'storage pool defects' that are often seen in grey platelet syndrome, Hermansky-Pudlak syndrome, and Chediak-Higashi syndrome.
Flow cytometry Platelets can be evaluated for functional defects using flow cytometry. This test uses lasers to determine proteins that are present on the platelet surface and how they change when the platelet is activated. Platelet flow cytometry is a highly specialized procedure available only in a few university hospital and reference laboratories to diagnose inherited platelet function disorders.
A blood sample is drawn though a needle from a vein in the arm. If you have a history of excessive bleeding, you should inform the healthcare practitioner drawing your blood. In general, no test preparation is needed. However, you may be instructed to refrain from taking drugs that can affect the results of these tests, such as aspirin, non-steroidal anti-inflammatory drugs NSAIDs , or any over-the-counter medications that contain drugs such as these.
Various platelet function tests are used to evaluate the ability of platelets to clump together and begin to form a clot. They may be used for a variety of reasons. Examples of some of the situations in which they may be used include:.
For a more detailed explanation of these tests, read the "What is being tested? Some other tests that may be done in conjunction with or as follow up to platelet function tests to evaluate platelet disorders include complete blood count CBC , platelet count , PT , PTT , D-dimer, and von Willebrand factor vWF.
One or more platelet function tests are ordered whenever a healthcare practitioner wants to evaluate platelet function. The interpretation of results of the various types of platelet function tests depends on why the tests were performed. Testing for coagulation factor deficiencies or abnormalities bleeding disorder tests in addition to clinical evaluation is often necessary to identify an inherited disorder or acquired condition as the cause of the dysfunction. Often, family studies may be required to determine if the abnormality is inherited or acquired.
Acquired platelet dysfunction — those that are not inherited — may be due to chronic conditions such as:. When a person is on an anti-platelet medication, such as aspirin, the results of testing reflect the platelet response to the medication. Platelet function testing is not a perfect reflection of the clotting process in the body in vivo.
A person with normal platelet function test results may still experience excessive bleeding or inappropriate clotting during and after a surgery. Most samples for platelet function testing are only stable for a very short period of time. Testing choices are often limited to what is locally available. There are several drugs that can affect the results of platelet function tests. Some of these include:. Typically, a hospital or laboratory will offer one or more tests but not a wide variety.
Since the sample must be tested promptly, your healthcare practitioner will choose from what is available. Rarely, if a healthcare practitioner wanted a particular type of test done, then it might be necessary for you to go to a clinic, hospital, or another city where that test is performed.
Bleeding Disorders Canadian Hemophilia Society: Emergency assessment of hemostasis in the bleeding patient. Int J Lab Hematol. Available online at http: Harrison, P and Lordkipanidze, M. Hematol Onc Clin N Am. Comparison of six major platelet function tests in predicting clinical outcome in patients undergoing coronary stent implantation. JAMA ; 8: Available online at https: High on-aspirin platelet reactivity as measured with aggregation-based, cyclooxygenase-1 inhibition sensitive platelet function tests is associated with the occurrence of atherothrombotic events.
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Blood Disorders, Chapter [On-line information]. Stanford Interventional Cardiology [On-line information]. Previously available online at http: Issues in Platelet Function Testing. Swiss Med Wkly PDF available for download at http: The bleeding time does not predict surgical bleeding. Blood , Jun ; Bleeding Time Revisited Blood , May ; Medscape Conference Coverage, based on selected sessions at the: Medscape General Medicine ;7 3: FDA k Summary [On-line information].
Contemporary Practice in Clinical Chemistry: Updated March