Differential Diagnosis

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Differential Diagnosis. Presented by M.A. Kaeser, DC Winter 2010. Introduction. Patients seek physician services for 2 reasons To establish the correct diagnosis To obtain the appropriate intervention, including prevention - PowerPoint PPT Presentation

Text of Differential Diagnosis

  • Differential DiagnosisPresented by M.A. Kaeser, DCWinter 2010

  • IntroductionPatients seek physician services for 2 reasonsTo establish the correct diagnosisTo obtain the appropriate intervention, including preventionTreatment provided for an incorrect diagnosis fails the patient to the same degree as does diagnosis w/o appropriate treatment

  • Process of Differential DiagnosisDiagnosis is obtained after considering a number of competitive etiologies and progressively eliminating themRational and intuitive skillsThe essence of cost-effective health careAn orderly approach is necessaryData acquisition, analysis with ranking of positive findings, construction of the diff dx, narrowing of diff dx by testing strategyAfter diagnosis, therapeutic intervention is designed and implemented

  • Acquisition of DataHistory and physical exam are the most essential components of the diff dx processAchieved by intuition and sensory inputVerbal and nonverbal clues help formulate the tentative diagnostic impressionsNonverbal example: oversized clothing from weight lossAll diagnostic decisions are dependent upon reliable data

  • Acquisition of Data: Chief ComplaintExplore thoroughlyPatient should review all relevant symptomsInterview reveals the patients level of expression and personalityPitfalls in the interview processCultural influences, attitudes, fears, ignorance and memory loss altering the reliability of the historianAsk branching questionsIntention is to amplify and distill various diagnostic hypotheses or hunchesPast medical, family and social history may reveal cluesROS provides information

  • Acquisition of Data: Physical ExaminationConcentrates on region of the chief complaint and any associated findingsGeneral survey physical examination is importantVital signs one of the most cost-effective tests Elevated temperature with back pain may indicate pyelonephritisAbnormal findings must be independent of their specific anatomic location, and separate from the designation or diagnosisPhysical examination answers the question, How sick or abnormal is this patient?

  • Acquisition of Data: Abnormal FindingOften will trigger additional physical assessmentsEx. T/S scoliosis in a very tall person may prompt a cardiac evaluation to exclude MarfansPatients examination should be considered ongoingSubsequent visits should allow for a brief review of the positive findings and identification of new findings or complications

  • Analysis and Ranking of Positive FindingsPertinent findings are listed in the order of apparent relevanceThis is point where diagnostic accuracy is compromisedImproper significance results in either too much, or too little, consideration for a given findingTime and natural course of a disease may alter the frequency and significance of a given findingPrimary or key findings demonstrate high sensitivity or specificityEx. Weakness in all extremities or quadriparesis suggests a stenosis of the spinal cord. Constipation or vertigo are nonspecific

  • Analysis and Ranking of Positive Findings: Common ErrorsArise when insufficient data are available as a result of careless interview or examination techniques (or the physicians knowledge is inadequate or lacks interpretive experience)Last case bias influences clinical reasoning due to recent diagnosis Avoid the tendency to force congruence with a diagnostic classification

  • System AssignmentPositive findings should be assigned to one or more of the physiological systemsAcute or chronic ambulatory pain syndromes arise in association with MSK and neurological systemsRadiculopathy, myelopathy, weakness, muscle atrophy and spinal segmental fixationGU systemM/C extraspinal source of referred pain to the lower T/S and L/SOther systemsEndocrine, cardiovascular, respiratory, GI and dermatological

  • Differential CategoriesMay be variable and arbitraryCategories include:NeoplasmInfectionVascularTraumaArthritideEndocrineCongenital

  • NeoplasmMost life-threatening Malignant neoplasms of the primary or metastatic variety must be suspected in any adult patient presenting with progressive spinal or pelvic painAverage delay in the diagnosis of skeletal metastasis is 10 monthsSuspicious findingsIntractable skeletal pain or pain persisting day and night for a duration exceeding 5 days

  • Neoplasm: Clues with Important ValuePhysical findings of weakness, unexplained fever, lymphadenopathy, organomegaly, or any progressive sensory or motor deficitLab findingsMicrocytic or macrocytic anemia, elevated sedimentation rate (ESR), hypercalcemia, elevated alkaline or acid phosphatase, proteinuria, and monoclonal gammopathy are associated with skeletal malignancyNegative lab tests and radiographs never exclude the possibility of skeletal malignancyPoor sensitivity of radiography limits its role in the early diagnosis of skeletal malignancy

  • InfectionCan mimic disorders of almost any etiologyCardinal clinical manifestationsAcute onset of fever, chills, adenopathy, malaise and myalgiaJoint infections in the appendicular skeletonClosed posttraumatic effusion that is warmSpinal infections (discitis)Considered when spinal or pelvic surgery is antecedent to progressive spinal pain and febrile patient

  • Infection: Constitutional SignsAnorexiaWeight loss MalaiseIV drug abusers and immunocompromised patients are prone to bone and joint infectionsLab findingsElevated WBC and ESR

  • VascularOften overlooked when acute pain evolves over hours or days following an abrupt onsetHeadaches esp. occipital, which are sudden and severe in the presence of altered consciousness or neurological deficits, herald a TIA or strokeThromboemboli in the pulmonary or coronary circulation give rise to progressive chest pain, tachypnea, tachycardia or SOBOften seen in legAneurysms of the abdominal aorta can erode the vertebral body giving rise to painPeripheral occlusive vascular disease Considered when signs of claudication are notedUnilateral edemaIn either extremity warrants consideration of vascular or lymphatic compressionBilateral lower extremity edema is a sign of congestive failure

  • TraumaFrequent source of ambulatory pain syndromesOften arises from vehicular or work-place accidents or from sports endeavorsLigamentous injury in the C/S must be carefully soughtAtlantoaxial instability can be excluded by flexion extension x-raysOccult fractures in the neural arches of the mid and lower C/S should be considered if severe posttraumatic cervical spine pain persists beyond 7 to 10 daysStress fracturesSkeletal pain provoked by activity and relieved by restFractures Accompanied by history of trauma and pain with the exception of neurogenic arthropathy (minimally painful, if at all)Pathological fracturesUsually suspected after radiological evaluation reveals features of bone destruction and/or soft-tissue masses

  • ArthritideSource of most patient diagnoses presenting with a pain syndromeMacrotrauma is often precipitating event of degenerative arthrosesMay be precipitated by aggregate microtrauma from inefficient postural controls or work-place stressesHallmark of a degenerative arthritideReproducible joint-based pain

  • Arthritides: Common ComplicationsVertebral columnDisc degeneration and herniation, segmental instability and spinal stenosisSigns: altered joint mobility, radiculopathy, referred pain, reflex sympathetic dystrophy, atrophy, spasticity, weakness or claudicationMyofascial trigger points are often located in neurofacilitated segments

  • Arthritides: InflammatoryRAASCharacterized by a history of pain in multiple bilateral joints Morning stiffnessSwelling

  • Arthritides: MetabolicGoutPseudo-goutRequire laboratory diagnosis and joint aspiration for confirmation

  • EndocrineAlso includes metabolic and nutritional disordersOne of the most challenging diagnostic categories to evaluateEndocrine glands and metabolism govern physiological activities throughout the bodyInspection often raises the question of an endocrine-metabolic disorderUsually arise due to excess or deficiency of hormone secretionTarget receptor responsiveness may be absent or elevated

  • Endocrine: Common EndocrinopathiesManifestationsWeakness, easy fatigability, growth abnormalities, hirsutism, weight loss or obesity and altered reproductive function (impotence, irregular menstrual cycles)DisordersOsteoporosis (m/c cause of spinal pain of metabolic origin)Diabetes mellitusHyper- and hypothyroidismHypoglycemiaDefinitive diagnosisLab testsSpecific hormone levelsAdvanced imaging

  • CongenitalAlso grouped with dysplasias and genetic disordersShort stature of dwarfismSpider-like hands and feet of MarfansHistory of recurrent fractures in OIMost significant congenital spinal anomaly is an unstable os odontoidiumDiagnosed by flexion/extension radiographs

  • Differential DiagnosisConstructed in order of declining probabilityInfluenced byAge, gender, race, disease prevalence, clinical featuresCommon sense, logic and intuition will eliminate the diagnostic possibilities and advace the probabilitiesBe specific (ex. Spinal stenosis, myofascitis of gluteus maximus)Lack of adequate findings results in a nonspecific diagnosis (this is o.k. since testing strategies will help to narrow diagnosis)Process involves significant negative or absent findings and the presence of positive findingsTry to include treatable conditions

  • Testing StrategyProceed with treatment versus employ testing proceduresDetermined by Level of certainty or confidencePresence of conditions capable of inflicting significant morbidity or mortalityCost effectiveness of further testingIf differential contains morbid or potentially fatal condition, you must rule out or c