識別診断 Differential diagnosis

differential diagnosis of atypical measles syndrome is similar to that of typical measles; however, the pleomorphism of the rash and the severe constitutional signs sometimes observed may suggest Rocky Mountain spotted fever, leptospirosis, hemorrhagic varicella, or meningococcal infection; other differential diagnoses include certain bacterial or viral pneumonias, collagen vascular diseases such as juvenile RA, and Kawasaki syndrome (mucocutaneous lymph node syndrome).

Even in typical polymyositis or dermatomyositis, a muscle biopsy is required for final diagnosis, thereby excluding the rare differential diagnosis of inclusion body myositis or postviral rhabdomyolysis.

diagnosis and differential diagnosis

For diagnosis and treatment, see differential diagnosis and Treatment of Rickettsial Diseases, above.

Asthma is the major consideration in the differential diagnosis and is the more likely diagnosis in a child > 18 mo of age, especially if previous episodes of wheezing and a family history of allergy have been documented.

differential diagnosis includes consideration of secondary growth failure due to malabsorption, congenital defects, renal failure, endocrine disease, or emotional deprivation.

Although the history may be helpful, differential diagnosis may be impossible in some cases.

Compulsive (psychogenic) water drinking may present a difficult problem in differential diagnosis.

It is valuable in the differential diagnosis of hyperthyroidism, which is discussed below.

A more difficult differential diagnosis is central hypothyroidism.

Anion gap: Calculation of the anion gap is often helpful in the differential diagnosis of metabolic acidosis (see Table 12-9).

VP should be considered in the differential diagnosis of acute porphyrias, especially if PBG deaminase activity is normal.

A directed physical examination can refine the differential diagnosis; eg, the finding of an enlarged liver in a patient complaining of dark, tarry stools may expand the previous consideration of gastritis or peptic ulcer disease to include cirrhosis with esophageal varices or GI cancer with liver metastases.

differential diagnosis

differential diagnosis includes lymphoma, in which multiple gastric ulcers occur, mucosa-associated lymphoid tissue (MALT) lymphoma (see below) with extensive infiltration of monoclonal B lymphocytes, Zollinger-Ellison syndrome with associated gastric fold hypertrophy, and Cronkhite-Canada syndrome, a mucosal polypoid protein-losing syndrome associated with diarrhea.

Some relatively common diseases must be considered in the differential diagnosis of acute abdominal pain.

Acute pancreatitis should be considered in the differential diagnosis of every acute abdomen.

The differential diagnosis of acute pancreatitis includes a perforated gastric or duodenal ulcer, mesenteric infarction, strangulating intestinal obstruction, ectopic pregnancy, dissecting aneurysm, biliary colic, appendicitis, diverticulitis, inferior wall MI, and hematoma of abdominal muscles or spleen.

CT is performed if the differential diagnosis includes appendicitis or an abscess.

However, in about 10% of cases, duodenal diverticula are responsible for symptoms (bleeding, pain and nausea caused by distention or inflammation), and they should be considered in the differential diagnosis of an acute abdomen.

differential diagnosis commonly involves peptic ulcer and its complications.

Elevations are specific and very sensitive for hepatobiliary disease, but they do not assist in differential diagnosis nor indicate prognosis.

The differential diagnosis includes extrahepatic biliary obstruction, chronic active hepatitis, primary sclerosing cholangitis, and drug-induced cholestasis.

The differential diagnosis includes cholangitis, pancreatitis, appendicitis, peptic ulcer, and pleurisy.

differential diagnosis includes Reiter's syndrome, Stevens-Johnson syndrome, SLE, regional enteritis (Crohn's disease), ulcerative colitis, ankylosing spondylitis, and herpes simplex infection, especially with recurrent aseptic meningitis.

In differential diagnosis, the lesions of rosacea are characterized by pustules and the absence of atrophy.

differential diagnosis includes polyarteritis nodosa, the vascular renal phase of SBE, SLE, lethal midline granuloma (ie, lymphoma), and rapidly or slowly progressive glomerulonephritis.

differential diagnosis

differential diagnosis of chronic low back pain may be difficult.

differential diagnosis is often based on the location of pain (see Table 60-2).

These tests are also valuable in making a differential diagnosis.

differential diagnosis in Children

differential diagnosis in Adults

differential diagnosis in patients with massive PE includes septic shock, acute MI, and cardiac tamponade.

When PI occurs, the differential diagnosis includes pneumonia, atelectasis, heart failure, and pericarditis.

Cavitary TB is not considered a lung abscess but must be remembered in the differential diagnosis.

differential diagnosis includes TB, sarcoidosis, Hodgkin's disease and other lymphoproliferative disorders, eosinophilic granuloma of the lung, desquamative interstitial pneumonitis, and collagen vascular disorders.

differential diagnosis includes emphysematous bullae, large lung abscess, and herniation of the stomach, colon, or, much less commonly, small bowel through the diaphragm.

differential diagnosis of pulmonary nodules includes foreign bodies, nonsegmental pneumonia, and endobronchial and focal pulmonary manifestations of TB, systemic mycoses, autoimmune disease, and metastatic disease caused by an extrathoracic primary cancer.

The reflex adapts or decays in neural hearing loss, and determining whether it adapts or decays, especially below 2000 Hz, aids in differential diagnosis of sensory and neural hearing loss.

differential diagnosis includes diphtheria, Vincent's angina (trench mouth), and infectious mononucleosis.

In such cases, the differential diagnosis must include streptococcal or staphylococcal pharyngitis.

General diagnostic patterns can expedite the differential diagnosis (see Table 127-1).

Similarly, a few common mechanisms of increased destruction (eg, sequestration by the spleen, antibody-mediated hemolysis, defective RBC membrane function, abnormal Hb) greatly aid in the differential diagnosis of hemolytic anemias.

Thus, the MCV has become the most important RBC index in the differential diagnosis of anemias, and confidence in the derived figures (especially Hct) has declined.

Automated-flow cytometry provides a new parameter in differential diagnosis: A histogram of anisocytosis (variation in cell size) can be automatically expressed as the coefficient of variation of the RBC volume distribution width (RDW).

differential diagnosis (see Table 127-4) includes Fe-deficiency, Fe-transport-deficiency, and Fe-utilization anemias, anemia of chronic disease, and the thalassemias (see Anemias Caused by Defective Hemoglobin Synthesis, below).

Although pica and especially pagophagia suggest Fe deficiency in the differential diagnosis of microcytic anemia, no pathognomonic symptoms or signs exist.

A sequential approach to the differential diagnosis is to consider the population at risk (eg, geographic, genetic, underlying disease) and then proceed through the likely potential mechanisms: (1) RBC sequestration resulting from changes in vascular complex (ie, hypersplenism or some form of extracorporeal circuit, such as renal dialysis), (2) immunologic injury (warm or cold antibody-mediated), (3) mechanical injury to the RBC membrane (RBC fragmentation), (4) changes in RBC structure (abnormal membranes), (5) metabolic abnormalities (enzymopathies), or (6) abnormal Hb states.

Table 130-4 lists laboratory tests for differential diagnosis, and Fig. 130-1 lists suggested steps in the evaluation of erythrocytosis.

The differential diagnosis depends on the clinical presentation.

Aplastic anemia, infectious mononucleosis, and vitamin B12 and folate deficiency should be considered in the differential diagnosis of severe pancytopenia.

differential diagnosis is simplified by immunophenotyping.

In differential diagnosis, the leukocytosis of patients with myelofibrosis is usually associated with nucleated RBCs, tear-shaped RBCs, anemia, and thrombocytopenia.