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Normal blood pressure In children buy generic alavert 10 mg line allergy testing insurance, hypertension is a relatively uncommon is defined as consistent blood pressure measure- finding and its presence often suggests some under- ments less than the 90th percentile compared with lying disease purchase alavert 10mg on line allergy medicine and breastfeeding. Unlike in adults, where hypertension blood pressure readings from a peer reference group. Stage 1 nosis, in children primary hypertension is considered hypertension is defined as typical blood pressure a diagnosis of exclusion. Regardless of its cause, sig- ³95th percentile with stage 2 or severe hyperten- nificant elevations of blood pressure can lead to acute sion exceeding the 99th percentile. Children with organ dysfunction, and the hypertensive child almost sustained blood pressure readings >30% above the always warrants a diagnostic evaluation while treat- 99th percentile for age, size, and gender are at par- ment is ongoing. In the hospitalized child, there is the ticular risk of developing acute sequelae from their additional burden of determining if hypertension is a high blood pressure and, even if asymptomatic, blood problem in itself or if it stems from another ongoing pressure control must be immediately addressed to illness or condition. Accurate measurement of blood pressure is essential Hypertension is relatively uncommon as the root for diagnosis and for allowing ongoing management cause of admission to the general pediatric ward or the decisions. Acute elevations of blood pressure are based on measurement by auscultation in an upper frequently categorized into hypertensive urgencies and extremity while sitting [1]. In spite of this, oscillo- hypertensive emergencies, the difference being the metric measurements of blood pressure are widely presence of actual end organ dysfunction in emergen- used because of the ease in obtaining these readings, cies. Oscillometric measurements congestive heart failure and impairment of renal func- of blood pressure are typically at least 5–10mmHg tion may also be seen. As secondary to severe hypertension is a rarer conse- a result, any high blood pressure measurements should quence. Although blood pressures from arte- admission for continuous infusion of antihypertensive rial lines should, ostensibly, be superior to measure- agents and close clinical monitoring. Although unlikely in the presence of signifi- Cuff size is another important factor that affects cant hypertension, if this occurs the diastolic blood accuracy of blood pressure measurement. Generally, pressure should be measured at the muffling, or fourth a cuff that is too small will overestimate blood pres- Korotkoff sound. Although there are cal assessments such as peripheral perfusion, will assist controversies regarding the most precise method for in allowing the clinician to gauge the child’s hemo- measuring cuff size [2, 4, 19], the recommendations dynamic status. This guideline delineates that hypertensive urgencies or emergencies, or in whom the width of the cuff bladder should be at least 40% of blood pressures have been chronically quite elevated, the arm circumference measured midway between the it is important to make sure that any therapy aimed at olecranon and acromion. This measurement also tends decreasing blood pressure does not result in too rapid to correlate with the bladder length covering 80–100% a fall from the aberrant baseline since this may trigger of the arm circumference. In these settings, the impor- should be available for both manual and oscillometric tance of being able to assess blood pressure reliably by blood pressure measurements. In the normal child with no aortic or lower extremity arterial compromise, read- Most hospitalized children with identified high blood ings from the lower extremities (thighs or calves) pressure have a secondary form of hypertension, should be higher than upper extremity blood pres- although as the incidence of obesity rises so too does sures. Although lower extremity readings may provide the incidence of primary, or essential, hypertension in information about blood pressure trends when com- all children [8, 16, 31, 33]. Although obesity and the pared with other lower extremity readings, these meas- metabolic syndrome result in measurable physiologic urements should not be used to determine if a patient changes including increased vascular endothelial actually has hypertension or if medication doses need activity, obesity-related hypertension in children is to be augmented. As noted earlier, auscultation is the modality that has The diagnostic evaluation of a hospitalized hyper- been used to create pediatric norms for blood pressure. The right arm is used both by convention outpatients or children on the general ward, the evalu- as well as to assist in the diagnosis of coarctation of ation should focus on the assumption of a secondary the aorta, as the left subclavian artery usually comes cause until proven otherwise. Somers with evidence of sustained or recurrent hypertension, been undiagnosed and any past history of unexplained especially in the face of adequate analgesia and seda- recurrent febrile illnesses should be elicited [38]. Glomerulonephritis often presents with a nephritic This evaluation can be done in a stepwise fashion syndrome with edema, hematuria, and hypertension and and individualized based on findings of the history, may be isolated to a primary renal condition or asso- physical exam, screening tests, and the child’s clinical ciated with systemic inflammatory disorders such as condition. Relevant historical fea- Children with more persistent significant elevations tures should focus on joint symptoms, edema, rashes, of blood pressure, as well as younger children with and unexplained fevers. Recent systemic infections hypertension, are more likely to have definable causes may also lead to postinfectious glomerulonephritis of their hypertension. An algorithm for the diagnostic complex, tuberous sclerosis, and neurofibromatosis. A evaluation of hypertension in the hospitalized child is strong family history of cardiovascular disease such provided in Fig. Moreover, normal blood pressures, pain or anxiety may play a role symptoms such as headaches and sleep disturbances are in hypertension as can agitation from rapid weaning of often associated with hypertension and may improve sedation after prolonged intubation or other procedures. Sweating, Similarly, in the child hospitalized with severe reactive palpitations, and flushing are associated with states airway disease, frequent administration of beta-agonists of catecholamine excess such as that accompanies a may be problematic. Height, weight, and body mass index should be meas- Interventions in the neonatal period, such as placement ured to assess for poor growth or to document an over- of umbilical catheters, or periods of hypotension or weight state or frank obesity. As outlined earlier, the diminished effective volume, may lead to renal hypop- accurate measurement of blood pressure is an essen- erfusion and subsequent renal scarring. Upper urinary tial part of the physical assessment of the child with tract infections, and especially repeated episodes of suspected or confirmed hypertension. In children with pyelonephritis in the first few years of life, may pre- an unclear etiology to their hypertension, blood pres- dispose to renal parenchymal scars that lead to renin- sure should be measured in all four extremities. Blood pressure in the lower extremi- end-organ damage, such as left ventricular hypertrophy, ties that is not higher than measurements in the upper arteriolar narrowing and hyperreactivity, and structural extremity is suggestive of a coarctation or other nar- and functional measures of endothelial dysfunction rowing of the aorta and is often associated with dimin- such as elevated carotid intimal medial thickness and ished femoral pulses. Previous the physical exam should also include fundoscopic, studies have shown that children presenting with hyper- cardiovascular, pulmonary, and neurologic exams. Somers abdomen should be auscultated for abdominal bruits alocorticoid excess is suspected as plasma renin activ- that, although uncommon, can accompany renovascu- ity is typically suppressed. As these studies are typi- dence of a systemic disease that may explain the elevated cally sent out to reference laboratories, their values are blood pressure. Similarly, several genetic syndromes not helpful in the acute management of hypertension. These include neurofibromatosis (café-au-lait with the initial screening studies, prior to use of potent spots, axillary freckling, Lisch nodules), tuberous scle- vasodilatory antihypertensives. An ultrasound provides infor- stature, shield chest, upturned mouth, webbed neck), mation about differential renal size, hydronephrosis, and Williams syndrome (overfriendly personality, echotexture, and cystic change and, thus, is a good cognitive impairment, prominent ears). As the medical condition stabilizes, scarring needs to be confirmed or is highly suspected. A urinalysis should be performed Doppler study does not, however, rule out renal artery on a freshly voided urine sample and, if the dipstick is stenosis, especially stenosis in smaller segmental positive for blood or protein, should include microscopy arteries not appreciated well by Doppler. For example, tachy- careful ophthalmologic exam may also give information cardia in the absence of pain or agitation suggests as to the chronicity of the child’s hypertensive state. Plasma renin activity and aldosterone levels are In the child with sustained blood pressures exceeding the helpful only if their results are unequivocally low or 99th percentile, diagnostic evaluation and therapy need high. The tempo and urgency Chapter 12 Hypertension in the Pediatric Intensive Care Unit 177 Table 12. The blood pressure Sodium nitroprusside is a powerful arteriolar and should be lowered by 20–30% in the first 2–3 h. For decades, its rapid onset of action the blood pressure is in a range that is not acutely dan- with short half life has made it a first-line option for gerous for the patient, the blood pressure should be continuous antihypertensive infusion. Nitroprusside lowered more gradually to at least the 95th percentile acts as a donor of nitric oxide, which mediates its reference blood pressure over the next several days or potent vasodilatory characteristics.

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The principal factor limiting xenotransplantation is immune rejection cheap alavert 10mg on line allergy testing eugene oregon, the destruction of donor tissue by the host immune system order alavert 10 mg allergy washington dc. Xenotransplant recipients have been rendered immunodeficient by irradiation, drug therapy, or surgical thymectomy in an attempt to inhibit the rejection process. The more commonly used immunodeficient mouse strains include the nude, scid, and beige genotypes. More recently, targeted mutations in genes involved in B- and T-cell development have produced new models of immun- odeficiency that resemble scid mice. Because scid mice display a major immune defect, they provide a unique biological setting that can be used to address major questions in the fields of gene therapy and xenotransplantation. This phenotype is the result of expression of a recessive gene mutation maping to mouse chromosome 16. The scid mutation results in defective rearrangement of immunoglobulin and T- cell receptor genes during differentiation of the respective cell lineages, thereby blocking the differentiation of B- and T-lymphocytic lineage committed progenitors. Older scid mice express leakiness and produce a small amount of murine immunoglobulin. The immune phenotype also can be influenced dramatically by genetic background, age, and microbial flora, complicating comparisons of experimental outcomes among different laboratories. A fade-out use of immunodeficient mice has been as a repository for human tissue, particularly human tumors. Both nude and scid mice can support transplantation and growth of a variety of human tumors. However, nude mice will not support the growth of all tumors grown in scid mice, possibly due to the presence of competent B cells in nude mice. The adopted transfer of human cells is followed by a period of growth and expansion with experimental manipulation in a manner not possible with human patients. Specific gene therapy protocols, employing varying target genes and delivery vehicles, can be systemati- cally evaluated for efficacy directly on human tissue in an in vivo setting. More sophisticated manipulations using immunodeficient mice also have been performed. The engraftment of a functional human immune system into scid mice has provided a powerful tool for studying the role of the human immune system in cancer, autoim- munity, and infectious disease. Several protocols involving engrafting thymus, liver, bone marrow, cord blood, and/or peripheral blood lymphocytes have produced xenotransplant models where engrafted human hematopoietic cells reconstitute a human immune system in the mouse. The successful ex vivo transduction of hematopoietic (see Chapter 6) progenitor cells and subsequent engraftment into scid mice has resulted in novel animal models for use in gene therapy research. Currently, for certain appli- cations, the usefulness of transgenic and gene-targeted mice has been limited based on the occassionally deleterious effects of engineered changes on gene expression and subsequent mouse development. Some mice with targeted mutations die in utero, suggesting that the affected gene plays a critical role in fetal development. This obviously is problematic in attempting to model a disease that occurs postnatally in humans. A solution is to generate models in which transgene expression or gene deletion can be targeted to specific tissues in adult animals. Tissue-specific transgene expression can be achieved by use of tissue-specific gene regulatory elements. Developmental expression of stage-specific gene expression can be produced in animals. However, temporal pattern of transgene expression may be dictated by the multiregulatory elements. In some cases, transgene expression can be induced by virtue of regions within the gene regulatory elements that bind to molecules and enhance transcription. Recently, several additional inducible systems have been examined where there is minimal trangene expression in the uninduced state and high-level trangene expression fol- lowing induction. The best established of these new systems employs tetracycline (Tc) as the inducing agent. Thus, a transgene whose expression would otherwise result in embryonic death would remain “silent” in utero until tetracycline was administered via injection or drinking water. In an additional approach, the viral cre/lox system recently has been employed to knock out specific genes in selected cell types of the adult animal (see also Chapter 5). Using this maipulation, gene deletion can be limited to a particular cell type in the mouse, rather than affecting all cells throughout devel- opment. A further refinement of this technique would involve placing cre gene expression under control of an inducible gene regulatory element. In this manner, the targeted gene would function normally in all tissues during development. But, cre expression and targeted gene deletion could be induced in specific adult tissues at a precisely selected time. This will involve changing the pattern of expression of multiple genes in a single animal. Currently, breeding between different transgenic and/or gene-targeted lineages has been used to produce animals with two or three gene changes. This approach, although in prin- ciple is unlimited, is inefficient and time consuming. Instead, it is now possible to introduce large changes into the genome in one step. At some point, it will be possible to introduce complete chromosomes into mouse cells. An advantage of large-scale genetic engineering is that multigenic disorders can be more effectively modeled in animals. Finally, there are many other animal species that have been used to create models of human diseases. Each has its own set of anatomical, biochemical, or physiologi- cal characteristics that make them well suited to examine specific human conditions. In view of the recent advances in animal cloning using somatic cells (see Chapter 2), it is certain that genetic manipulation of these species will become easier and each species will find an increasingly important place in studies involving molecu- lar medicine. The ideal model for the study of somatic gene therapy should exhibit the same genetic deficiency as the disease being modeled. In general, the greater the sim- ilarity between the mouse mutation and the mutation as it occurs in humans, the greater the likelihood that the mouse will produce a reliable model of the human disease. These new mutations then can be mapped in the mouse genome, and perhaps the human gene location inferred through synteny homologies. Transgenes generally permit assessment of the phenotypic consequences of dominant acting genes because the mouse retains normal copies of all endoge- nous genes. With a low frequency, the vector will undergo homologous recombination with the endoge- nous gene.

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It is obtained from the animal protein sources in the diet as well as being synthesized by the liver purchase generic alavert on-line allergy testing pictures. Physiology: As a major constituent of bone order alavert master card allergy medicine loratadine 10mg, calcium plays a vital role in the structure of the body. It also has Diagnostic Value: Elevated and decreased choles- important physiologic functions involving the trans- terol concentrations may occur from a number of mission of nerve impulses, the permeability and excit- physiologic influences and different diseases; how- ability of all membranes, the activation of enzyme ever, the diagnostic value of this test in birds appears systems (eg, blood clotting), calcification of egg shells to be poor. Very high cholesterol concentrations usu- and contraction of the uterus during oviposition. There is a reasonable agreement in Method: Most currently used assays are based on the the values among the most commonly used meth- Jaffe reaction. Lipemia or hemolysis of the sample can interfere with photometric methods of measurement, giving falsely Physiology: Blood creatinine is derived mainly from 11 elevated values. This is less likely to occur with the catabolism of creatine found in muscle tissue. Physiology: Glucose is continuously required as an It is freely filtered and reabsorbed in the tubules. In periods of starvation, glucose is increasingly de- rived from the breakdown of fats and proteins, pri- Diagnostic Value: There is a slim margin between marily from muscle tissue, through gluconeogenesis the physiologic and pathologic levels of creatinine. All plasma glucose is For many analyzers, physiologic values are below the filtered from the blood through the renal glomeruli detectable range. Interestingly, 73 hours of starvation in pigeons in- Physiologic Influence: Normally, creatinine produc- duces hyperglycemia rather than starvation hypo- tion is relatively constant and is minimally affected 57 glycemia. This finding has important consequences by catabolism of dietary or tissue proteins. Theoreti- for avian anesthesia and gastrointestinal surgery, as cally, the pool of creatine from which creatinine is presurgical fasting varying from four hours (empty- liberated depends on the total muscle mass. How- ing of the crop) to 24 hours (emptying of the entire ever, in all avian species that have been investigated, gastrointestinal tract) can be advantageous. Pro- the reference interval for creatinine has been be- longed fasting is not recommended in birds that tween 0. Diagnostic Value: Glucose is often a part of a labora- Pathologic Changes: Severe kidney damage can 25,43,73 tory panel even though pathologic changes in lead to increased creatinine levels, especially if the 36 birds are seldom detected. Juve- A rise in plasma glucose concentration starts during nile budgerigars were found to have higher concen- the scotophase, reaching peak values early during the trations than adults. Afternoon plasma glucose concentra- Pathologic Changes: Increased plasma inorganic tions in birds that are fed early during the photophase phosphate levels can be seen in some cases of severe are significantly higher when compared to fasted 2,36,73 kidney damage due to vitamin D hypervitami- birds. For example, increases occur after meals, decreased plasma inorganic phosphate levels may with excitement or stress or because of decreased occur from hypovitaminosis D (calcium level also glucose usage (diabetes mellitus). Iron is transported should not be used because they interfere with the in the plasma attached to a β-1-globulin known as formation of the phosphomolybdate complex. A recent report shows a failure to correlate serum iron levels with liver biopsy and subsequent Method: Most assays for inorganic phosphate rely on toxicologic analysis for iron. It is a major constituent of bone and a vital nificantly lower values than their free-ranging coun- cellular component, playing important roles in the terparts. Very little data different standards are used (eg, human, bovine, from birds is available. Because it is impossible to have a have little importance in diagnosing hemochroma- 74,75 species-specific standard for all species presented to tosis, but insufficient research has been performed. This enzyme functions in compensated and already calibrated in scales ex- the digestion of fat in the diet. For ters yielded higher values than the biuret method, diagnostic purposes, a blood sample from a repre- with the temperature-compensated instrument be- sentative of the same species should be included for ing consistently higher in readings than the non- comparison. Temperature stress (hypothermia or sults from the refractometer and the biuret methods hyperthermia) is associated with nitrogen loss, in- may not be possible in some species. Hypoproteinemia can reflect reduced synthesis Physiology: Most plasma proteins, with the excep- caused by chronic hepatopathies, malabsorption tion of immunoglobulins and protein hormones, are caused by chronic enteropathies (enteritis, tumors, synthesized in the liver. They form the basis of organ parasitism), increased loss caused by proteinuria due and tissue structure, operate as catalysts (enzymes) to renal disease, blood loss and malignant tumors in biochemical reactions, are regulators (hormones) (rarely seen in birds) or starvation and malnutrition. The biological activity of tious diseases that stimulate production synthesis of proteins for these various functions is dependent gamma globulin. The proteins are the yolk precursors (vitel- Electrophoresis logenin and lipoproteins), which are synthesized in Sample: Serum is most commonly used for protein the liver and transported via the plasma to the ovary electrophoresis in mammals, so fibrinogen is not in- where they are incorporated in the oocyte. Hemolysis will affect electro- phoresis results, and heparinized plasma is often Diagnostic Value: Total protein is often used as an 50,54,72 used to prevent this problem. Determi- nation of plasma protein concentrations may be of Method: Electrophoresis is used to separate differ- value in diagnosing gastrointestinal, hepatic or renal ent types of plasma proteins, making it possible to diseases. Furthermore, plasma proteins will be ab- determine their relative proportion in a particular normal in infectious diseases that cause a stimulation sample. Although determination of supported on a specific matrix, is placed in an electri- plasma proteins seldom leads to a specific diagnosis cal field, causing the different protein fractions to (eg, in the case of monoclonal gammopathies), it will migrate at varying speeds toward the anode based on help the clinician to evaluate the severity and pro- their relative charge. The length and height of each peak dietary protein, temperature stress, state of hydra- ithin the pattern indicates the relative amount of a tion, hemorrhage and inflammation. Some immunoglobulins, including IgM and IgA, also migrate in the β-globulin range. The γ-globu- Sample: Serum and lipemic specimens should be lin fraction is mainly composed of immunoglobulins 66 warmed to 37°C and vigorously mixed prior to analy- (IgA, IgM, IgE and IgG). Diagnostic Value: In healthy birds the albumin frac- Method: Usually, triglycerides are enzymatically de- tion is the largest protein fraction. Often albumin concentrations are decreased in these situ- Physiology: Triglycerides are the major storage form ations. The combined effect of these changes is a of lipids, and are a major energy source. Examples of diseases with a decrease in the A/G ratio are egg-related peritonitis, and Diagnostic Value: Triglyceride values have been in- chronic infectious diseases such as aspergillosis, psit- sufficiently evaluated in birds. Serum or plasma protein electrophoresis can be used to monitor response to treatment. When the bird Physiologic Influence: Triglyceride levels may vary responds favorably, an increase in the albumin con- based on climate, hormone influence, diet and gen- centration and a decrease in the globulin concentra- der. Increases may occur during starvation, particu- tion can be observed, which leads to normalization of larly in obese birds. In birds with liver failure, extremely shown to elevate triglyceride concentrations in some species. Gastrointestinal Pathologic Changes: Egg-related peritonitis has and renal diseases can also lead to severe hypoprote- been associated with high concentrations of trigly- inemia. Because triglyceride values are Physiologic Influence: Physiologic factors that may determined based on enzymatically released glycerol, change the protein concentration and therefore affect these values may be falsely elevated after exercise or protein electrophoresis results include gender, age, following any event that causes increased levels of blood glycerol (eg, catching birds in an aviary).

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Nonetheless buy 10mg alavert mastercard allergy and treats, these results are very encouraging buy 10mg alavert free shipping allergy treatment for pollen, as any improvement over a placebo can have profound real-life benefits. The single largest trial was conducted at 176 centers in Italy and included 2,044 patients. Acupuncture There is some clinical research showing that acupuncture can facilitate recovery from a stroke. Specifically, acupuncture can often help stroke patients perform self-care better, can mean that patients require less nursing and less rehabilitation therapy, and can possibly cut health care costs. Possible mechanisms of its effects include stimulation of nerve cell regrowth, facilitation of improved nerve cell function, reduction of poststroke inflammatory reactions, and prevention of nerve cell death. Given its safety and possible benefits, acupuncture is very much worth the effort. That being the case, appropriate prevention of further strokes involves following the recommendations in the chapter “Heart and Cardiovascular Health. The primary therapeutic goal in the recovery from a stroke is to enhance the blood and oxygen supply to the brain as well as improve nerve cell function. In autoimmune diseases the immune system attacks the body’s cells and tissue, resulting in inflammation and tissue damage. There are often times of remission interrupted by periods of illness (called flares). It most often affects women in their childbearing years (ages 15 to 35) and is also more common in women of non-European descent. Speculation and investigation have centered on genetic factors, abnormal bowel permeability, lifestyle, nutritional factors, food allergies, and microorganisms. However, research indicates that this predisposition requires an environmental trigger. Another important way in which a vegetarian diet may be helpful is that is has a higher alkalinity than a meat-based diet. Eight of the 10 patients reported improvements in overall well- being, fatigue, energy, and/or other symptoms. For the group as a whole, there was a significant improvement in the physician’s overall assessment of disease activity. However, research indicates that this predisposition requires an environmental trigger. Botanical Medicines Please consult the chapter “Rheumatoid Arthritis” for more information. Symptom relief can also be attained through the use of nutritional supplements, botanical medicines, and physical medicine techniques. However, do not abandon natural measures, because they will actually enhance the effectiveness of the drugs, allowing for lower dosages when drugs are necessary, while providing a foundation for healing by addressing the underlying causative factors and utilizing modalities that are both safe and beneficial in long-term use. Please see the chapter “Rheumatoid Arthritis” for a more complete discussion of our recommended treatments. Diet The first step is a therapeutic fast or elimination diet, followed by careful reintroduction of individual foods to detect those that trigger symptoms. Although any food can cause a reaction, the most common are wheat, corn, dairy products, beef, foods in the nightshade family (tomatoes, potatoes, eggplant, peppers), pork, citrus, oats, rye, egg, coffee, peanuts, cane sugar, lamb, and soy. After all allergens have been isolated and eliminated, a vegetarian or Mediterranean- style diet rich in organic whole foods, vegetables, cold-water fish (mackerel, herring, sardines, and salmon), olive oil, and berries and low in sugar, meat, refined carbohydrates, and animal fats is indicated. Positive results from other tests may indicate that treatment for intestinal permeability, dysbiosis, and environmental toxicity is advisable. Uterine Fibroids • The majority are without symptoms but may be associated with vague feelings of discomfort, pressure, congestion, bloating, and heaviness; can include pain with vaginal sexual activity, urinary frequency, backache, abdominal enlargement, and abnormal bleeding • Abnormal bleeding in 30% of women with fibroids Uterine fibroids are bundles of smooth muscle and connective tissue that can be as small as a pea or as large as a grapefruit. However, because they disrupt the blood vessels and glands in the uterus, they can cause bleeding and loss of other fluids. Uterine fibroids are classified according to their location, as follows: • Submucosal (just under the lining of the uterus) • Intramural (within the uterine muscle wall) • Subserosal (just inside the outer wall of the uterus) • Interligamentous (in the cervix between the two layers of the broad ligament) • Pedunculated (on a stalk, either submucosal or subserous) Causes Increases in local estrogen (specifically estradiol) concentration within the fibroid itself are thought to play a role in the development and growth of fibroids. Concentrations of estrogen receptors are higher in fibroid tissue than in the surrounding tissue. In addition to an excess of estrogen production within the body, a strong case can be made for the role of the most significant environmental factor assaulting female hormonal health—compounds known as xenoestrogens. These compounds are also known as endocrine or hormone disrupters, environmental estrogens, hormonally active agents, estrogenic substances, estrogenic xenobiotics, and bioactive chemicals. Examples of xenoestrogens include phthalates (used in plastics), pesticides, tobacco smoke by-products, and various solvents. Xenoestrogens enhance or block the effects of estrogen in the body by binding to estrogen receptors. They also promote a shift from healthy estrogen breakdown products to cancer-causing estrogen metabolites. Therapeutic Considerations Reducing the size as well as the symptoms of uterine fibroids with natural medicines is easily accomplished in most cases. Unfortunately, this statement is supported more by the clinical experiences of naturopathic physicians than by scientific evidence, though the approach is scientifically rational—that is, if uterine fibroids are caused by an excess of estrogen produced in the body as well as the effects of xenoestrogens, it makes sense that reducing estrogenic influences should shrink uterine fibroids. Keep in mind that as women pass through menopause there is less estrogen and so there will also be a tendency for the fibroid to shrink on its own. Diet The most important dietary recommendations are to eat a high-fiber diet rich in phytoestrogens (plant estrogens) and to avoid saturated fat, sugar, and caffeine. These simple changes can dramatically reduce circulating estrogen levels and reduce estrogen’s influence on the fibroid. One study looked at what happened when women switched from the standard American diet (40% of calories from fat; only 12 g fiber per day) to a healthier diet (25% of calories from fat; 40 g fiber). That’s a good thing, because when phytoestrogens occupy the receptors, estrogen can’t affect cells. By competing with estrogen, phytoestrogens cause a drop in estrogen effects, and are thus sometimes called antiestrogens. Great sources of phytoestrogens include soy and soy foods, ground flaxseed, and nuts and seeds. These dietary recommendations have extreme significance not only in treating uterine fibroids but also in reducing endometrial cancer. Women with uterine fibroids have a fourfold increase in the risk of endometrial cancer. In a case-control study of a multiethnic population (Japanese, white, Native Hawaiian, Filipino, and Chinese) examining the role of dietary soy, fiber, and related foods and nutrients in the risk of endometrial cancer, 332 women with endometrial cancer were compared with women in the general multiethnic population, and all women were interviewed by means of a dietary questionnaire. Similar reductions in risk were found for greater consumption of other sources of phytoestrogens, such as whole grains, vegetables, fruits, and seaweed. The researchers concluded that plant-based diets low in calories from fat, high in fiber, and rich in legumes (especially soybeans), whole grain foods, vegetables, and fruits reduce the risk of endometrial cancer. These dietary associations may explain at least in part the lower rates of uterine cancer in Asian countries than in the United States. Soy isoflavones appear to be selective in terms of the tissues in which they have an estrogenic effect and the tissues in which their effect is antiestrogenic. Soy phytoestrogens do not appear to have an estrogenic effect on the human uterus and may in fact help shrink uterine fibroids due to an antiestrogenic effect. We recommend moderate but not excessive soy consumption in the range of 45 to 90 mg soy isoflavones per day.