Ebook Ferris best test - A practical guide to laboratory medicine and diagnostic imaging (2nd edition): Part 2

(BQ) Part 2 book Ferris best test - A practical guide to laboratory medicine and diagnostic imaging presents the following contents: Imaging and laboratory tests and algorithms, aseptic necrosis, cardiomegaly on chest radiograph, dysuria,...

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1 Dhingra R et al: C-reactive protein, infl ammatory conditions, and cardiovascular disease risk,

Am J Med 120:1054-1062, 2007.

2 Jeremias A, Gibson M: Narrative review: Alternative cause for elevated cardiac troponin levels

when acute coronary syndromes are excluded, Ann Intern Med 142:786-791, 2005.

3 Jones JS: Four no more: The PSA cutoff era is over Cleveland Clin J Med 75:30-32, 2008.

4 McKie PM, Burnett JC: B-type natriuretic peptide as a marker beyond heart failure:

Speculations and opportunities, Mayo Clin Proc 80(8):1029-1036, 2005.

5 Pagana KD, Pagana, TJ: Mosby’s Diagnostic and Laboratory Test Reference, ed 8, St Louis,

Mosby, 2007

6 Sarmak MJ et al: Cystatin C concentration as a risk factor for heart failure in older adults,

Ann Intern Med 142:497-505, 2005.

7 Wu AHB: Tietz Clinical Guide to Laboratory Tests, Philadelphia, WB Saunders, 2006.

12 Alkaline phosphatase elevation p.

13 Alpha1-antitrypsin defi ciency p.

24 Aneurysm of abdominal aorta p.

25 Antinuclear antibody (ANA) positive p.

26 Antiphospholipid antibody syndrome p

These algorithms are designed to assist clinicians in the evaluation and ment of patients They may not apply to all patients with a particular disease or disorder, and they are not intended to replace a clinician’s individual judgment

treat-Please note that specifi c fi ndings in the patient’s history and physical tion may signifi cantly alter any of the proposed testing sequences

154 Pelvic pain, reproductive age woman p.

155 Peptic ulcer disease p

156 Peripheral arterial disease p

157 Peripheral nerve dysfunction p.

179 Refl ex sympathetic dystrophy (RSD) p

180 Renal artery stenosis p

181 Renal insuffi ciency p

188 Rotator cuff tear p

189 Sacroiliac joint pain p

190 Salivary gland neoplasm p

CT of abdomenwith contrast orultrasound in young womenand children

CBC withdifferential

Ancillarylab tests

CT-guided drainage

of abscess and Gram’s stain andC&S of abscessaspirate

• Blood type and antibody screen to identify Rh-negative patients who may need Rh immunoglobulin

Diagnostic Algorithm

Suspected abruptioplacentae Initiate continuous fetalheart rate monitoring

Laboratory evaluationObstetrical ultrasound

Diagnostic

Inconclusive

Esophagealmanometry

Upper endoscopy torule out malignancyand strictures

• CT of brain and auditory canal with

IV contrast if MRI is contraindicated

Detailed neurologicexam with specialattention to thecranial nerves

MRI of brain andauditory canalswith gadolinium

HIV antibodytest

Negative

Positive

Repeat in4–6 weeks

T-lymphocytesubset analysis

Viral load

• Suppression test with oral glucose

• Serum phosphate (increased)

• Serum calcium (increased)

Diagnostic Algorithm

6 Acromegaly

Suspectedacromegaly

SerumIGF-I

Normal

Elevated

Diagnosisunlikely

Suppressiontest with oralglucose(failure tosuppress GH

to <2 ng/mLafter 100 g

of oral glucose

is consideredconclusive)

MRI ofpituitary andhypothalamus

Suspected actinomycosis

Chest x-ray

Identification

of abscess,

Abnormal CT of chest, head, abdomen and pelvis

Negative Consider other diagnosis

I&D of abscesses, excision

of sinus tract

Stain and culture

of isolated

“sulfur granules”

7 Actinomycosis Diagnostic Imaging

• Isolation of “sulfur granules” (nests

of Actinomyces species) from tissue

specimens or draining sinuses

Ancillary Tests

• CBC

Diagnostic Algorithm

• Blood and urine cultures

• Bronchoalveolar lavage (in selected tients who respond poorly to therapy)

pa-Diagnostic Algorithm

8 Acute Respiratory Distress Syndrome

SuspectedARDS

Chest x-ray

ABGs

CBC withdifferential,blood andurine cultures

Hemodynamicmonitoring

Figure 3-2 ARDS due to extrapulmonary disease Chest radiograph 21⁄2 days after postoperative hemorrhage There is diffuse ground-glass opacifi cation, slightly greater on the right than the left For unknown reasons, the left apex

is spared Incidentally noted are signs of barotraumas—pneumomediastinum

and subcutaneous air in the neck (From Grainger RG, Allison DJ, Adam A, Dixon AK, eds: Grainger & Allison’s Diagnostic Radiology, ed 4, Churchill Livingstone, Philadelphia, 2001.)

IV cosyntropin; measurecortisol level at baseline,

30 min, 60 min

Low cortisol level(<18 mcg/dL)Elevated cortisol level

(>18 mcg/dL)

ACTH level

No adrenal insufficiency

ElevatedNormal/decreased

Primary adrenalinsufficiencyAdrenal insufficiency

secondary to pituitaryinsufficiency

• If cushingoid appearance, obtain overnight dexamethasone suppres-sion test

• If signs of virilization or feminization, order 24-hour urine for 17-ketosteroids and plasma dehydroepiandrosterone sulfate (DHEAS)

• If hypertension is present with associated hypokalemia, evaluate for aldosteronism

Diagnostic Algorithm

10 Adrenal Mass

Suspectedadrenal mass

MRI or CT

of adrenalgland

Cysticappearance

Homogeneousappearance

Nonhomogeneous

or large mass(>6 cm)

Ultrasound Simplecyst

Ancillarylab tests

Surgicalresection

• Adrenal scan with iodocholesterol (NP-59) or 6-beta-iodomethyl-19-norcholesterol

Suspectedhyperaldosteronism

PAC/PRA

≥20 andPAC >15ng/dL

Negative

Diagnosis excludedPositive

Aldosterone suppression test(2 L of normal saline infusionover 4 hours followed bymeasurement of plasma aldosterone level)

Plasma aldosteronelevel >10 ng/dL

Primary aldosteronismconfirmed

Probable bone source of elevation

CT or ultrasound of liver, ancillarylab tests

X-ray of pelvis, serum calcium, phosphateConsider Paget’s disease of bone, osteomalacia,neoplasm, hyperparathyroidism

Diagnostic Inconclusive

Consider liver biopsy

Elevated alkaline phosphatase (ALP), adult patient

Repeat ALP, obtain serum GGT

Elevated ALPElevated GGT

Probable hepatic source of elevation

Elevated ALPNormal GGT

Chestx-ray Abnormal

Serum alpha-1 antitrypsinlevel, C-reative protein

Low serum alpha-1 antitrypsinlevel, Normal C-reative protein

Pulmonary function testsHigh Resolution Chest CT

Genotype identification Diagnosis confirmed

• Viral hepatitis serology

• GGT, alkaline phosphatase, bilirubin

• Antimitochondrial antibody (AMA), anti–smooth muscle antibody (ASMA), antinuclear antibody (ANA)

No further evaluation

at this time, repeat in3−6 months

CT or ultrasound of liver,ancillary lab tests

Diagnostic Non-diagnostic

Consider liverbiopsy

ALT/AST Elevation

• Consider fatty liver in obese patient (urge weight loss)

• Stop potential hepatotoxins (e.g., alcohol, statins, niacin, acetaminophen)

• Examine for stigmata of liver disease (e.g., jaundice, heptomegaly, nodular liver, ascites)

Stigmata of liver diseasepresent

Physical exam unremarkable

Lab Evaluation

Best Test(s)

• None

Ancillary Tests

• TSH, B12 level, methylmalonic acid

• VDRL, HIV (selected patients)

• Basic metabolic profi le

Diagnostic Algorithm

Suspectedcognitivedefects

Folstein’s Mini-MentalStatus Exam

Score >23

Score <23

Diagnosisunlikely

Repeat in

6 months

TSH, B12

level, VDRL,basic metabolicprofile

CT/PET of brain(selected cases)

• MRA of cerebral circulation

• Echocardiogram (r/o embolic source)

• MRI of brain with diffusion-weighted imaging (P/O INFARCT)

• ANA

Diagnostic Algorithm

Amaurosisfugax

CarotidDoppler

Normal

Significantstenosis

BrainMRA

Ancillary lab testsLipid panel ESR

17 Amebiasis Diagnostic Imaging

Suspectedamebiasis

Stool examfor O+P × 3

CT of liver if liverabscess is suspected

Normal sexualdevelopment

Serum prolactinlevel

Hypothyroidism(primary)

Hypothyroidism(secondary)

MRI of brain

Elevated MRI of pituitary

Positive(pregnancy)

Elevated LH Elevated DHEAS Normal or decreased FSH

Elevated FSH, normal prolactin

Normal/decreased FSH, elevated prolactin

• Rectal biopsy (positive in ⬎ 60%

of cases) to demonstrate amyloid deposits in tissue

Ancillarylab tests

NegativePositive

Diagnosis confirmed

Subcutaneous fataspiration andCongo red staining

Rectal biopsy

NegativePositive

Diagnosis confirmed Diagnosis unlikely, seek

alternate diagnosis

• MRI of brain and spinal cord

• Modifi ed Barium swallow to evaluate aspiration risk

• B12 level, TSH, HIV, lead level

• Serum protein IEP

• Muscle biopsy in selected patients to rule out myopathy

Diagnostic Algorithm

21 Amyotrophic Lateral Sclerosis

Suspected ALS(diagnosis is generallymade on clinical grounds)

EMG and nerveconductionstudies

• Serum B12 level, RBC folate level

• ALT, AST, gammaglutamyl transpeptidase (GGTP)

Rule out hemolysisRule out blood loss

Ancillary labs

Coombs’ testStool for OB x 3

DiagnosticInconclusive

Bone marrowexamRule out alcoholabuse

Measureserum iron,TIBC, ferritinlevel

Low serumiron, low TIBC,elevated ferritin

Low serumiron, highTIBC, lowferritin

Normal serumiron, normalTIBC, normalferritin

Anemia ofchronic disease

Iron deficiencyanemia

Hemoglobinelectrophoresis

Normal Abnormal

Basophilicstippling noted

on RBCs

ElevatedhemoglobinA2

LowhemoglobinA2

Lead poisoning

or sideroblasticanemia

thalassemiatrait/disease

Beta-thalassemiatrait/disease

Diagnostic Imaging

Best Test(s)

• Ultrasound of abdominal aorta is

best initial screening test; CT is

more accurate test

Ancillary Tests

• CT of abdominal aorta with IV contrast for preoperative imaging and size estimation and to diagnose perforation/tear

• Angiography for detailed arterial anatomy before surgery

Ultrasound

of abdominalaortaDiagnostic

Negative

CT of abdominalaorta for estimation

of size within 3 mm

Angiography

of abdominalaorta if surgery

is indicated

Homogeneous pattern Speckled pattern Nucleolar pattern Cytoplasmic pattern Jo-1 or PM-1 Anticentromere pattern

Rule out SLE, drug-induced Rule out SLE, MCTD, RA, Sjögren’

Positive anti-Smith Positive anti-RNP Positive anti-SS-A (Ro) or positive anti-SS-B (La)SLE MCTD or SLE Sjögren’

Diagnostic Algorithm

Suspectedantiphospholipidantibody syndrome(hypercoagulablestate and/or morbidity with pregnancy)

Ancillarylab tests toexclude otherhypercoagulablestates

Ancillary diagnosticimaging based onpresentation (e.g.,compressive ultrasound

in suspected DVT)

Negative

Anticardiolipin

Ab, lupusanticoagulantPositive

Diagnostic Imaging

Best Test(s)

• CT (sensitivity 83%-100%); CT of aorta is generally readily available and performed as the initial diagnostic modality in suspected aortic dissection

Chest x-ray (mayreveal widenedmediastinum in60% of cases,displacement

of aortic intimalcalcium)

ECG (maysuggest LVH,pericardialeffusion, acute inferior wall MI)

CT with IV contrast, transesophagealechocardiogram, MRI, or angiography(tests of choice depends on clinical circumstances and availability)

Tear DeBakey Types

Stanford Types

Figure 3-3 Aortic dissection (From Weissleder R, Wittenberg J, Harisinghani MG, Chen JW: Primer of Diagnostic Imaging, ed 4, St Louis, Mosby, 2007.)

Spiral CT ofappendix andlaboratoryevaluation

Ultrasound ofabdomen/pelvis

in children andwomen ofreproductive ageplus laboratoryevaluation

Diagnostic

Equivocalresults

Ancillary Tests

• CT with contrast for early diagnosis

in suspected infection of spine, hips,

or sternoclavicular and sacroiliac joints

Lab Evaluation

Best Test(s)

• Joint aspiration, Gram stain and C&S

of synovial fl uid (gonococcal culture

• Lyme titer (in endemic areas)

• Examination of joint fl uid for crystals (uric acid, calcium pyrophosphate)

Diagnostic Algorithm

29 Arthritis, Infectious (Bacterial)

Suspectedinfectiousarthritis

Ancillary lab testsand plain x-rays

of affected joint

Joint aspiration,Gram’s stain, C&S

of synovial fluid, exam

of fluid for crystals

• Ultrasound and ERCP when worms

in pancreatobiliary tract are suspected

Examination ofstool for ascariasis

ova, Ascaris Ig4

Ab by ELISA,ancillary lab tests

Ancillary diagnosticimaging studies

• Serum LDH, protein, albumin

• CBC, ALT, AST, BUN, creative

Diagnostic Algorithm

31 Ascites

Suspectedascites

Ultrasound ofabdomen/pelvis

Diagnosticparacentesis

Serum/ascitesalbumin gradientBloody fluid

ElevatedamylaseElevated neutrophilcount

Elevated(≥1.1g/dL)

Decreased(<1.1g/dL)

Cirrhosis,alcoholichepatitis,cardiacfailure,portal veinthrombosis,myxedema,Budd-Chiarisyndrome

CT of abdomen/

pelvis to rule outneoplasm

Pancreaticascites

Pancreaticascites, biliaryascites,nephroticsyndrome,peritonealcarcinomatosis,peritoneal

TB, bowelobstruction/

infarction

• Bone scan if MRI is contraindicated

or not readily available

• Plain fi lms of affected joint usually insensitive in early course

Plain x-rays

of affected joint

Diagnostic

Negative or equivocal

MRI of affected joint

A

B

Figure 3-6 Aseptic necrosis of the hip in a renal transplant

recipient A, Early changes consisting of low intensity oblique lines are noted by magnetic resonance imaging B,

Late changes of AVN by radiograph show narrowing of the hip joint space, sclerosis of the femoral head, and fl attening

of the left femoral head (From Johnson RJ, Feehally J:

Comprehensive Clinical Nephrology, ed 2, St Louis, Mosby, 2000.)

• Plain radiographs of spine

• CT scan of LS spine if MRI is contraindicated

• Ultrasound or CT of abdominal aorta if AAA is suspected

Detailed neuro exam focusing on “red flags”: major trauma, minortrauma in elderly or osteoporotic patient, suspected infectious process(immunosuppression, IV drug use), history of cancer, age >50 or <20,progressive neuro deficit, bladder dysfunction, saddle anesthesia (caudaequina syndrome), fever, weight loss, pulsatile abdominal mass

No red flags

Suspectdegenerativechanges, strainConservativetreatment for4–6 weeks

ImprovedNot improved

Positive (fracture,neoplasm)

Plain films of spine

SuspectedneoplasmSuspected

AAASuspectedspinalfracture

Suspectedcaudaequina

CBC, ESR, plainradiograph,bone scan

Ultrasound

of abdominalaorta

Plainfilms

Negative

MRI or

CT scan

MRIPositive

UrgentMRI ofspine

CT ofabdominalaorta

33 Back Pain, Acute, Lumbosacral (LS) Area

of affectedlower extremity

Direct > indirectdirect ≥ 0.5 mg/dlIndirect > direct

direct < 0.5 mg/dl

Ancillarylab testsAncillary lab

tests, CBC

Very high alkalinephosphatase, normal/elevatedALT, AST, PT (INR)

Very highALT, AST,normal/elevatedalkalinephosphatase, PT

Rule outobstructionRule

out viralhepatitis

Rule outautoimmunehepatitis

Rule outtoxins

PainlessPainful

CT ofabdomen(rule outneoplasm)

Ultrasound

of abdomen

HepatitispanelANA

Normal labs,isolatedbilirubinelevation

DecreasedHb/Hct,elevatedMCV

Rule outGilbertsyndromeRule out

hemolysis

• Factor VIII, IX assay

• Bleeding time or platelet function analysis (PFA) 100 assay

PT, PTT

Normal PT,normal PTTNormal PT,

elevated PTTElevated PT,

Consider deficientplatelet coagulantactivity

Factor VIII,factor IX

to rule outhemophilia orvon Willebrand’sdisease

TT

NormalElevated

Factors

II, V, XFibrinogen

immunoassay

of breast

CBC withdifferential

I&D of abscess C&S and Gram’sstain of abscess

contents

MRI of breastwithout contrast

is procedure ofchoice for diagnosis

Breast ultrasound ifMRI is contraindicated

Implant

Fibrous capsule Normal

Implant Inverted teardrop sign

Implant Radiating folds

Figure 3-7 Breast implant rupture (From Weissleder R, Wittenberg

J, Harisinghani MG, Chen JW: Primer of Diagnostic Imaging, ed 4,

St Louis, Mosby, 2007.)

Suspicious lesion

Negative/

Breast

Breast ultrasound

Solid mass

Cystic Cystaspirationand cytology

Nipple discharge Palpation and mammography

Bloody discharge

Nonbloody discharge

Ultrasound and surgical referral

Breast ultrasound

Aspiration of cystic lesion

Galactogram

Mass detected Surgical referral

Prolactin level, TSH

Elevated prolactin Elevated TSH

Thyroxine replacement MRI pituitary