Physical examination for drug induced malnutrition

Definition::

Physical examination should thin point clinical and biochemical sign of several diseases States including gastrointestinal diseases,, symptoms and conditions that may be related to malnutrition.. Many of the symptom may  be  nonspecific for mal nutrition but together with dietary and medical history can identify potentially modifiable nutritional risks.

MALABSORPTION:

Maldigestion may arise from many drug -related factors certainly include used and abuse of laxatives and gastric antacid products. The farmer markedly decrease gastrointestinal transit time (e.g bisacodyl[Dulcolax]©l] mineral oil). The letter change the pH to decrease adsorption of dietary folate (aluminums and magnesium hydroxide [Maalox], sodium bicarbonate).

Drugs specifically to treat gastrointestinal disorder (such as ulcerative colitis and Crohn disease) may have the undesirable side effect of contributing to folate deficiency by decreasing hydrolysis of dietary folate polyoxometalate. This can be counterbalanced by use of folate supplementation either with vitamin tablets or folate fortified foods that require less hydrolysis. And other positive step is not to take drug such as sulfasalazine with meals because the drug is thought to interfere with folate absorption.  Patients with celiac disease or with hemolytic anemia maybe particularly to drug- folate malnutrition.

Vitamin B12 is another vitamin particularly gastro intestinal drugs. Deep preparation of vitamin B12 for absorption and the amount absorbed are dependent on several factors. Dietary  B12 is found only in foods of animal origins; thus vegan vegetarians are particularly vulnerable to deflation.

Dietary B12 must be bound to intrinsic factor that is produced in the stomach. The vitamin also requires and environment for the binding to occur. Potassium chloride supplements, particularly the slow,- release form may yield and abnormal schilling test suggest of vitamin B12 impairment. Secondary malabsorption can occur with the chronic use of H2 histamine receptor antagonists. Various formulation of h2 antagonist and proton pumps inhibitors, including nonprescription strength, prevent intrinsic  factors (lf) binding.

 Later on, the absorption of  B12 -IF  require the basic environment found in healthy Mucosa near the ileocecal value to complete its cycle.. maximum B12 observation occurs at pH 6.6 and has been said to be absent below a pH of 5.5. The last step in the absorption of B12 occur in the lower small intestine pro ximal to the ileocecal value.. Gastrointestinal disease and specially surgery in this area of the small intestine can greatly reduce the absorption of vitamin B12 and the re absorption of bile acid. Thus, fat malabsorption may also occurs, thus lowering absorption of the fat- soluble vitamins as well as B12.

ANEMIAS:

Vitamin B12 deficiency that arise from the lack of intrinsic factor has been termed pernicious anemia, a fatal diseases where the original treatment was the feeding of desiccated livers. Once the process of vitamin B12 absorption was understood  injection of B12 provided to relief from this megaloblastic anemia.

With the low cost of injection; physician no longer need to order laboratory test is to confirm the diagnosis of pernicious anemia; they can simply treat patients with monthly injections. B12 deficiency may occur as part of achlorhydric anemia, a form of microcytic anemia secondary to a lack of guested  acid. This form of anemia is more likely to occur in the elderly or in adults who heavily use over the counter (OTC) antacids. Other drugs that antagonists of folate may lead to a secondary B12 deficiency. This occurs because a lack of a late drive metabolic pathways that require B12 producing a consequent increase in the need for B12 at a time when intake is level or declining and stores are depleted. Heavy alcohol use may further complicate these interactions because it constitutes other mechanism by which b vitamin requirements are increased.

Anemia may also arise from a little recognized side effect of taking vitamin C supplements in amounts greater than 1 gram daily or as a constituent of multivitamin mineral supplements according to Herbert. The actions of the vitamin C, iron and other antioxidant nutrients in high dose supplement may convert vitamin B12 into analogues that are useless to humans. Supplementary vitamin B12 may not be sufficient protection. Herbert recommends tad person taking mega doses of vitamin C b checked regularly for vitamin B12 deficiency or stop taking hi door supplements. Others dis agree that excess vitamin C destroys vitamin B12 but the upper limit of daily vitamin C intake is set at 1 g to avoid other adverse events.

Multiple forms and causes of anemia may exist but exact diagnosis may not be attempted. The busy practitioner who sees a low hemoglobin value base simply prescribe iron supplements specially in the elderly. In reality iron supplementation may provide no positive effect on the  anemia but may instead pose are risk of iron overload in the elderly patients. In addition iron supplements as well as supplements of other divalent and minerals may complex with other drugs the patient takes reducing effectiveness of those agents through decrease absorption.

The assessment of anemia should begin with a simple fingerprint and microscopic bloods smear examination to distinguish between microcytic and macrocytic anemia as well as hypochromic and  normochromic erythrocytes. If the erythrocytes are judged microcytic the question of occult bleeding secondary to drugs or lack of dietary protein should be raised. Another potential form of microcytic hypochromic anemia is the anemia of chronic disease associated with some other major diseases such as rheumatoid arthritis, inflammatory bowel disease, cancer and some vascular disorders.

 The hypochromic cell appears pale due to lack of iron. If the erythrocyte is judged to be macrocytic distinction needs to be made as to the potential for folate, B12 and B6 deficiency as well as copper deficiency. A dietary and drug history can be used to judge likely causes and corrective action can be taken that will  resolve the anemia.

Drugs that interfere with folate or pyridoxin status can create a deficiency of B12 as well. A lack of one vitamin may shift metabolism to and alternate pathway which increase the need for other vitamin. This is specially true for the B6 vitamins found in many important pathways including the Krebs cycle.

Anemia main also developed from the use of single mineral supplements that creates and unbalance competition for other minerals there by creating a relative deficiency. 

For example use of zinc supplements may induce a copper deficiency. Drugs that  chelate minerals such as  penicillamine used in Wilson's disease to reduce serum copper may also chelates other minerals.

Neuropathies:

Neuropathy may occur as a result of vitamin deficiency or toxicity. Until recently water soluble vitamins were thought to be in capable of producing toxicity. A number of Neuro logic diseases such as pre menstrual syndrome , carpal tunnel disease, foot drop and others were treated with mega doses of various B vitamins including pyridoxine. Physician prescribing B6 in 2  gram doses begin to recognize a neuropathy that largely but slowly resolved after cessation of B6 regimen.

Drug induced imbalances of vitamin B6 or vitamin B12 can lead to the development of neuropathy. Common to both are the slow development of paraesthesia, numbness and the development of paresis of the lower limbs. Vibration sense may be reduced specially in vitamin B12 deficiency. Vitamin B12 deficiency has often been spotted by the burning feet syndrome, muscles soreness in the legs and  atrophy of the peritoneal muscles. It is often difficult to diagnose drug induced  by biochemical means because the B6  antagonist may well produced the deficiency by inducing hyper excretion of the vitamin in the urine.

 Urinary measures are commonly used to screen for water soluble vitamin deficiency but are not particularly helpful in drug induced deficiency States if the drugs action is to increase urinary excretion. Vitamin B6 deficiency does not commonly occur in isolation. Other B6 vitamin deficiency is most notably riboflavin deficiency also affect vitamin B6 status and share clinical science such as  stomatitis, glossitis, irritability, depression and  confusion. Riboflavin is needed in the metabolism of vitamin B6.

Dermatitis:

Although drug induced dermatitis is seldom of nutritional origin important nutrient deficiencies have been first identified by dermatitis specially in early days of total parenteral  and enteral nutrition. 

vitamin B6. antagonist such as live dopa in large doses can produce a suberic dermatitis and pellagra otherwise of light exposed areas of the body such as (collar bone, neck, arm, hand, feet and legs). Pellagra may be cause by a lack of several B vitamins but most notable is lack of  niacin. Pellagra still found in the US today usually associated with poor diets and other conditions such as alcoholism that may for the aggravate a poor intake. in dermatitis that not only involves the outer skin but also alters the oral mucosa the tongue becomes a bright red color.

 Does the tongue and other gastrointestinal symptoms should be checked for causation by impaired niacin status. If accompanied by neurological symptoms of depression, apathy, loss of memory  may well arise from nutrient efficiency of one or more B vitamins.Riboflavin deficiency may develop with long term use of several psychotherapeutics drugs including some of the new year generation of tricyclic anti depressants and antipsychicotic drugs.

The classic phenothiazine increase the need for riboflavin. Patience requiring such drugs frequently present with limited dietary intake for several weeks peer to hospital admission. The elderly or substance abusers specially those recently dieting stand at greater risk for lack of dietary riboflavin. Riboflavin is a vitamin with unlimited number of rich food  choices.

 The absence of or limited intake of milk products should serve as a Red flag to monitor riboflavin status. Clinical symptoms associated with riboflavin deficiency are not specific and may represent other causes including sub marginal intakes of several other vitamins. Thus screening for milk and meet intake becomes a primary means of identifying the readily corrected dermatitis induced by these drug nutrient interactions. Antitubercular and anti malarial drugs may also induced dermatitis secondary to nutrient deficiencies of B vitamins.

Chronic diseases:

Several chronic diseases may lead to long term malnutrition known as marasmus or cachexia. Most notable among these are cardiac cachexia, cancer cachexia, chronic obstructive  pulmonary disease. HIV AIDS  and weakness due to a number of disease states in the elderly. The term Sarcopenia has been coin to describe the slow study loss of lean muscle mass secondary to severity in activity, disease states and aging. The addition of appropriate exercise prescription to a well design nutritional care plan should be considered. Is dish therapy is prove inadequate and other potential therapeutic approach is the use of appetite stimulating drugs including :

Prednisone

Dronabinol 

Oxandrolone

Megestrol 

These drugs brings both benefit and risk two nutritional care plan. Prednisone has been in use longer and has proved effective for short term stimulation. It carries risk of hypokalemia, muscle weakness, cushingoid features, hyperglycemia, immune suppression and other pathologies. these risk make Prednisone a poor choice for stimulating appetite in patients with diabetes mellitus or  HIV/ AIDS.

Dronabinol a derivative of Marijuana has been shone to improve appetite but does not appear to bring any significant weight gain. Taken before meals appetite may be improved but avoidance of alcohol is recommended. Nausea and vomiting at the side effects. Other risk include mental changes such as euphoria, somnolence, dizziness and confusion.

 Another new habitat stimulant is megestrol acetate sold under the brand name menace  which has been shown to improve appetite, body weight, well being and quality of life when combined with exercise and nutrition. Risk include impotent, vaginal bleeding and deep vein thrombosis.

Bone disease:

A number of drugs can induced such bine diseases as osteocalcin in adults and ricket in children. The causation derived from secondary interference with uptake of vitamin D, calcium and other vitamins only recently recognized as involved in bone metabolism for example vitamin k. Other diseases States most notable end stage renal disease can make people much more vulnerable to the nutritional problems inherent with these drugs. The absence of dairy products in the diet should serve as a Red flag to monitor vitamin D and calcium status in drug regiment such as anti tuberculosis drugs ,anti convulsant and anti lipidemic.

End stage renal disease and liver disease diminished number of hormones that are produced either in lower amount or not in an activity form. This deficiency may required the use of several nutrients supplement specially in activity form. For example the active form of vitamin D is often given during dialysis combined with administration of intra luminal phosphate binder. Care must be taken not 

 to give excess vitamin D or magnesium supplements with this regimen because impaired renal function may lead toxicity.

How to assess drug related malnutrition?

Which drug cause malabsorption?

Which drugs are related to anemia?

Which drug cause bone problem?

Which drugs are related to gastrointestinal disturbances?