By A. Norris. Worcester Polytechnic Institute.
Sarcoidosis Frequently associated with hilar and mediasti- (Fig C 5-2) nal lymph node enlargement order vardenafil 10mg overnight delivery, which often reg- resses spontaneously as the parenchymal disease develops buy vardenafil 10mg overnight delivery. Bronchiectasis Irreversible dilatation of the bronchi related to a (Fig C 5-3) variety of causes buy vardenafil online, especially centrally obstructing lesions, infection or inflammation, congenital disorders, and pulmonary fibrosis. Diffuse increase in intersti- tial markings radiating in a bronchovascular distribution with tramlines (arrows) and peribronchial cuffing (arrow- head). Pulmonary Langerhans More prominent in the upper lung zones (sparing cell histiocytosis the bases). Tuberculosis Bronchiectasis and fibrosis may produce a localized honeycomb pattern in the upper lobes. Connective tissue disorders More prominent at the bases and usually asso- (Fig C 5-6) ciated with progressive loss of lung volume. Ankylosing spondylitis Rare manifestation that exclusively involves the upper lobes and resembles the fibrosis and bronchiectasis that may develop secondary to tuberculosis. Intervening small areas of lucency produce the appearance of a honeycomb lung, especially in the right upper lobe. Neurofibromatosis Additional manifestations include skin nodules, (Fig C 5-8) multiple bullae, scoliosis, and mediastinal neurofibromas. Chylous pleural effusion and pneumothorax are common, and sclerotic (occasionally lytic) bone lesions may occur. Coned view of the left lower lung demon- strates a honeycomb pattern, with small emphysematous areas combined with fibrosis and fine nodularity. Diffuse honey- comb pattern that is slightly more prominent in the upper lung zones. The draining bronchus may show irregular Central calcification and “satellite” lesions are thickening or even frank stenosis. Histoplasmoma Round or oval, sharply circumscribed nodule Most frequently in the lower lobes. Often associated Central calcification is common, and satellite calcification of hilar lymph nodes. Other fungal diseases Usually a single, well-circumscribed nodule Actinomycosis, blastomycosis, coccidioidomycosis, (Fig C 6-5) (may be multiple in coccidioidomycosis). In the absence of a central nidus of calcification, this appearance is indistinguish- able from that of a malignancy. Acute lung abscess Round, often ill-defined mass that predo- Bilateral in more than 60% of cases. Cavitation is (Fig C 6-7) minantly involves the posterior portions of the very common (irregular, shaggy inner wall). Single fairly well-circumscribed, mass- Fig C 6-4 like consolidation in the superior segment of the left Histoplasmoma. Large right middle lobe abscess containing an air-fluid level (arrows) in an intravenous drug abuser. The remaining 75% arise centrally in the bronchial lumen and cause segmental atelectasis or obstructive pneumonia. Hamartoma Solitary, well-circumscribed, often lobulated Serial examinations may show interval growth. Popcorn calcification (multiple punctate endobronchial lesion (10%) may cause segmental calcifications in the lesion) is virtually atelectasis or obstructive pneumonia. Although this “Rigler notch” sign was initially described as being pathogno- monic of malignancy, an identical appearance is commonly seen in benign processes. The mass is indistinguishable from other benign or malignant processes in the lung. Bronchogenic carcinoma primarily lymph node enlargement is common, especially involves the upper lobes with rare calcification and in oat-cell carcinoma. Hematogenous Single (25%) or multiple (75%) lesions that are Represents approximately 5% of asymptomatic metastases generally well circumscribed with smooth or solitary pulmonary nodules. Calcification is rare (Fig C 6-12) slightly lobulated margins and lower lobe (only in osteogenic sarcoma or chondrosarcoma). Conversely, patients with melanoma, sarcoma, or testicular carcinoma are more likely to have a solitary metastasis than a bronchogenic carcinoma. Well-circumscribed solitary nodule containing characteristic irregular scattered calcifications (popcorn pattern). Non-Hodgkin’s lymphoma Single or, more commonly, multiple nodules May be a manifestation of primary or secondary that often have fuzzy outlines and strands of disease. Hilar or mediastinal adenopathy is increased density extending into the adjacent usually associated. Multiple myeloma Sharply circumscribed, extrapleural mass Usually represents spread into the thorax of a (plasmacytoma) producing an obtuse angle with the chest wall. There is a second huge nodule (black arrows) that was not appreciated on the previous examination because it projected below the right hemidiaphragm. May cause bronchial obstruction with peripheral atelectasis or obstructive pneumonia. Carcinoid Well-defined, round or ovoid mass that may Carcinoid tumors are sometimes located distal to (Fig C 6-14) have a lobulated margin. Pulmonary hematoma Single or multiple, unilocular or multilocular, Results from hemorrhage into a pulmonary (Fig C 6-15) round or oval mass that may occasionally be parenchymal laceration or a traumatic lung cyst. Usually in a peripheral subpleural May communicate with the bronchial tree (air-fluid location deep to the area of maximum trauma. Generally shows a slow, progressive decrease in size (may persist for several months). Lipoid pneumonia Sharply circumscribed, smooth or lobulated Inflammatory reaction to aspirated oils (especially (Fig C 6-16) mass that primarily occurs in the dependent mineral oil). The lesion may have a may radiate outward from the periphery of the shaggy border and simulate carcinoma. After a stab wound, a homoge- neous kidney-shaped opacity (arrow) developed in the supe- rior segment of the left lower lobe. Sharply demarcated granulomatous- lipoid mass (arrows) simulating a neoplastic process. Rheumatoid necrobiotic Single or, more commonly, multiple smooth, Rare manifestation of rheumatoid lung disease that nodule well-circumscribed nodules that predominantly tends to wax and wane in relation to subcutaneous occur in a peripheral subpleural location. Bronchogenic cyst Solitary round or oval, smooth, sharply circum- Approximately two-thirds of bronchogenic cysts (see Figs C 23-3 and C 23-4) scribed mass with a lower lobe predominance. The cyst is homogeneous until a communication is established with contiguous lung (usually the result of infection). Intralobar bronchopulmonary Round, oval, or triangular mass that typically Enclosed in visceral pleura of the affected lung. An intralobar sequestration is supplied by a systemic artery and drains via the pulmonary veins. Extralobar Well-defined, homogeneous mass that is related Enclosed in its own visceral pleural layer (therefore bronchopulmonary to the left hemidiaphragm (above or below it) in seldom infected or air containing). About 50% of the patients have hereditary hemorrhagic telangiectasia (Rendu- Osler-Weber disease).
The ratio of total body water to surface area increases progressively upto about the age of 12 years 10 mg vardenafil fast delivery, but the absolute volume of body water is highest in males between the ages of 1 to 40 years vardenafil 20mg. Fat contains little water cheap vardenafil amex, so the thin individual has a greater proportion of water to total body weight than the obese person. The lower percentage of total body water in females correlates with the relatively large amount of subcutaneous fat and small muscle mass. An extremely obese individual may have 25 per cent to 30 per cent less body water than a thin individual of the same weight. The extracellular fluid, which represents 20 per cent of the body weight, is divided into (i) intravascular fluid (this represents 5 per cent of body weight) and (ii) interstitial or extracellular fluid (which represents 15 per cent of body weight). It should be remembered that intracellular fluid is larger subdivision and constitutes 70 per cent of total body water, whereas the extracellular water amounts to about 30 per cent of total body water and actually forms the suitable environment for the cells of the body. This water forms part of the protoplasm of the cells and is distributed in many small compartments or cells separated from each other by two cell membranes and layer of interstitial fluid. The largest portion of this intracellular water is within the skeletal muscle mass. As the females possess smaller muscle mass, the percentage of intracellular water is lower in females than in the males. If the chemical composition of the intracellular fluid is studied, it will be found that potassium and magnesium are the principal cations, whereas the phosphates and proteins are the principal anions. The intracellular concentration of potassium is approximately 125 mEq/L, magnesium is approximately 40 mEq/L and sodium is about 10 mEq/L. The concentration of phosphates is about 150 mEq/L in intracellular fluid, whereas protein constitutes 40 mEq/L of intracellular fluid. It can be divided into 3 subdivisions — (i) intravascular fluid (which is situated within the blood vessels) constitutes 7 per cent of total body water or 4 per cent of the body weight in normal adult; (ii) the interstitial or extravascular fluid (which lies outside the blood vessels and around the cells of the tissues of which it forms the immediate environment) constitutes 17 per cent of total body water or 7. The volume of the extracellular fluid can be measured by the dilution of a substance which passes freely through the walls of blood capillaries but does not enter into the cells of the body. The substances which have been used are inulin, thiocyanate, mannitol, thiosulphate, radioactive chlorine, bromine or sodium etc. Blood volume can be measured directly by dilution principle using red cells labelled with radioactive chromium (51Cr). The most important cation of extracellular fluid is sodium (which constitutes 140 mEq/L), whereas potassium (5 mEq/L), calcium (3 mEq/L) and magnesium (2 mEq/L) are the other cations available in the interstitial fluid. There are minor differences in ionic composition between the plasma and interstitial fluid due to difference in protein concentration. As the plasma contains higher protein content (organic anions), the total concentration of cations is higher in plasma than in the interstitial fluid. This intake is derived from two sources — (a) exogenous source and (b) endogenous source. About 1,200 ml water is drunk everyday from various beverages, whereas about 1,000 ml is derived from solid foods. During starvation this amount is supplemented by water released from the break down of body tissues. It must be remembered that water requirements of children are relatively greater than those of adults as (i) the water content is higher in respect to their total body weight, (ii) the metabolic activity is greater in children due to growth and (iii) the immature kidneys of the children are poor in concentrating ability. This amount of urine is excreted to get rid of the products of catabolism and end products of metabolism. In diarrhoea this amount is multiplied by the number of stools as also their fluidity. The insensible water loss through the skin is not from evaporation of water from sweat glands but from water vapour formed within the body and lost through the skin. The loss from the skin varies in accordance with the atmospheric temperature and humidity, muscular activity and body temperature. In case of hyperventilation and increased respiratory rate this loss is increased. Salt is also excreted by sweat which represents a hypotonic solution of salt with an average sodium concentration of 15 mEq/L. The sodium concentration in sweat however is exceeded to 60 mEq/L in unacclimatized individuals. The insensible fluid lost from skin and lungs is in fact pure water and does not contain any salt. Various gastrointestinal secretions contain various amounts of salts which of course are reabsorbed, except a small amount which is excreted with faeces. Sweat is a major source of loss of salt in tropical countries and this amount varies considerably according to the temperature and humidity of the environment. Whether sweating is noticeable depends on how rapidly it evaporates, which in turn is related to the humidity as well as to the temperature of the environment. But such high rate of sweating cannot be maintained for long and the rate falls down even if the individual is exposed to heat for more time. The sweat glands are partly under the influence of adrenal cortical hormones and the composition of sweat varies greatly, so much so that average figures cannot be given. Sodium concentration may vary from 6 to 85 mEq/L but is always lower than the plasma concentration. But the potassium concentration varies from 5 to 21 mEq/L and is always higher than that of the plasma. Concentrations of sodium and chloride in sweat are related also to the intake of these ions and usually decline when their body contents fall. When the salt intake increases, the concentrations of sodium and chloride in the sweat rise. About 100 mEq of sodium is excreted in the ur ine in normal individuals in temperate climate. This amount varies considerably according to the circumstances and normal kidneys have the power to reduce sodium excretion to less than 1 mEq/day. Excretion of urine and of sodium depends on glomerular filtration, which depends on the renal blood flow. Desoxycorticosterone acetate causes sodium retention by the tubules regardless of the sodium concentration in the plasma. The most powerful conservation of sodium is effected by aldosterone which is about 30 times as effective as desoxycorticosterone acetate. Release of aldosterone depends on dietary intake of sodium and its secretion falls when sodium intake rises. It probably acts mainly on the distal tubules, though it may also have effects on the proximal tubules. The fluid deficit is not water only, but water and electrolytes in approximately the same proportion as they exist in normal extracellular fluid. The cardiovascular symptoms and signs are mainly due to decrease in plasma volume e. There are certain other symptoms and signs reflected in the gastrointestinal system and general tissues.
If the excessive gas is passed rectally best order vardenafil, stools for occult blood purchase vardenafil us, stools for ovum and parasite vardenafil 20 mg without a prescription, and stool cultures should be done. If these are negative, a barium enema may be done and that may be followed with a small bowel series. A quantitative stool-fat analysis should be done to determine if there is steatorrhea, and if so, the workup would proceed (page 482). Hydrogen breath testing is useful in detecting lactase deficiency and other carbohydrate intolerance and bacterial overgrowth. Localized erythema would suggest phlebitis, gout, osteomyelitis, cellulitis, ingrown toenail, and paronychia. Achilles bursitis and tendonitis may be associated with Reiter’s syndrome and ankylosing spondylitis. Hallux valgus, hammertoe, hallux rigidus, arthritis, and displaced fracture are the main causes of a deformity of the foot. Diminished arterial pulses would make one think of arterial embolism, peripheral arteriosclerosis, and diabetes. The presence of loss of sensation to touch and pain should make one think of peripheral neuropathy and tarsal tunnel syndrome. Numbness or loss of sensation in the third and fourth toes is often associated with a Morton’s neuroma. If the peripheral pulses are diminished, Doppler studies and angiography should be considered. Stress fractures, Achilles tendonitis, and tarsal tunnel syndrome are common in runners. It is wise to refer the patient to an orthopedic surgeon or podiatrist before ordering expensive diagnostic tests. For example, a pes cavus may be associated with a peroneal muscular atrophy, poliomyelitis, and Friedreich’s ataxia. Amyotrophic lateral sclerosis and progressive muscular atrophy may also cause foot deformities. The finding of poor peripheral pulses would suggest that the lesion is secondary to ischemia from arteriosclerosis, Buerger’s disease, diabetic arteriolar sclerosis, familial hyperlipidemia, and cryoproteinemia. The presence of good peripheral pulses should make one look for a neurologic explanation for the ulcer, and if there is diminished sensation to touch and pain in the periphery, peripheral neuropathy is very likely. A history of diabetes makes the diagnosis of diabetic arteriolar sclerosis very likely. The presence of good peripheral pulses should prompt one to do a smear and culture of material from the lesion, and if this is positive, then the diagnosis is made. We would consider, in addition to the normal bacteria, blastomycosis, sporotrichosis, maduromycosis, and syphilis. A nerve conduction velocity study of the lower extremities will be helpful in differentiating neurologic causes. Femoral angiography may be valuable in determining the exact level of the lesion and whether it can be approached surgically. It may also be a normal process as the frontal air sinuses develop over the years. In children, forehead enlargement may be due to hydrocephalus, rickets, congenital syphilis, and a large hematoma. When other signs of acromegaly are present, serum growth hormone level should be measured. An elevated sedimentation rate coupled with an increased Free T suggests subacute thyroiditis. If there is a response, the patient probably has tertiary hypothyroidism (a lesion in the hypothalamus) or T3 thyrotoxicosis. The same holds true for a low free thyroxine except, in addition, one may need to order ultrasonography of the thyroid, a needle biopsy, or exploratory surgery. If there is dysuria, one should consider cystitis, urethritis, prostatitis, bladder calculi, and tuberculosis of the bladder. If there is no dysuria, then a bladder neck obstruction from conditions such as prostatic hypertrophy or urethral stricture might be considered. If there is fever along with frequency of urination, this could be due to a systemic condition, but it is more important to look for pyelonephritis. A sterile sample of the urine should be sent to the lab for culture regardless of whether the urinalysis is normal. If the urine volume is substantially increased, the workup may proceed for polyuria (see page 400). If the 24-hour urine volume is normal, a pelvic and rectal examination must be done for a mass that might be pressing on the bladder. Even if the pelvic and rectal examination is negative, pelvic ultrasound may disclose a pelvic mass. The next step would be to catheterize for residual urine or order ultrasonography of the urinary bladder. If the residual urine is large, bladder neck obstruction is probably the problem, and prostatic hypertrophy, median bar hypertrophy, and urethral stricture must be considered. If a spastic neurogenic bladder is suspected, order cystometric tests and a neurology consult. The rectal examination may disclose anal fissures, hemorrhoids, or perirectal abscess. Turner’s syndrome and testicular feminization are two of the conditions that may be associated with these abnormalities. Childhood sexual molestations and marital difficulties are among the conditions that may be found on a careful history. If abnormalities are found on these examinations, referral to a gynecologist or a proctologist can be made. If the pelvic and rectal examinations are normal, the patient should probably be referred to a psychiatrist or psychologist for treatment. If there are abnormalities of the secondary sexual characteristics, the clinician may undertake studies of these disorders, but referral to an endocrinologist is probably more cost-effective. An abnormal neurologic examination should make one think of multiple sclerosis, peripheral neuropathy, muscular dystrophy, Parkinson’s disease, Huntington’s chorea, and a host of degenerative neurologic conditions. The findings of a painful limp should make one suspect hip, knee, or an ankle joint pathology. Characteristic gaits include the short-stepped shuffling gait of Parkinson’s disease, the ataxic gait of multiple sclerosis and cerebellar disorders, the reeling, clownish gait of Huntington’s chorea, the pelvic tilt of muscular dystrophy, and the steppage gait of peripheral neuropathy. The patient has a normal neurologic examination and has no difficulty maintaining balance while sitting down, but there is total inability to walk or stand without reeling about. If there is a painful limp, x-ray of the hip, knee, or an ankle on the affected side should be performed. If multiple sclerosis is suspected, a spinal tap for myelin basic protein or gamma-globulin levels should be done.