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AbAntibody
AbnAbnormal
AFBAcid-fast bacillus
AgAntigen
AIDSAcquired immunodeficiency syndrome
ALTAlanine aminotransferase
ANAAntinuclear antibody
ASTAspartate aminotransferase
CBCComplete blood cell count
CFComplement fixation
CHFCongestive heart failure
CIECounterimmunoelectrophoresis
CKCreatine kinase
CNSCentral nervous system
CSFCerebrospinal fluid
CXRChest x-ray
CYPCytochrome P450
DiffDifferential cell count
EDTAEthylenediaminetetraacetic acid (edetate)
ELISAEnzyme-linked immunosorbent assay
GIGastrointestinal
GNRGram-negative rod
GNCBGram-negative coccobacillus
GPCGram-positive coccus
GVCBGram-variable coccobacillus
HLAHuman leukocyte antigen
IgImmunoglobulin
IMIntramuscular(ly)
INRInternational Normalized Ratio
IVIntravenous(ly)
MinMinute
MNMononuclear cell
MRIMagnetic resonance imaging
NNormal
NegNegative
NPONothing by mouth (nil per os)
PCRPolymerase chain reaction
PMNPolymorphonuclear neutrophil (leukocyte)
POOrally (per os)
PosPositive
PTHParathyroid hormone
RBCRed blood cell
RPRRapid plasma reagin (syphilis test)
SIADHSyndrome of inappropriate antidiuretic hormone (secretion)
SLESystemic lupus erythematosus
T3Triiodothyronine
T4Tetraiodothyronine (thyroxine)
TSHThyroid-stimulating hormone
VVariable
VDRLVenereal Disease Research Laboratory (syphilis test)
WBCWhite blood cell
WkWeek
YrYear
↑Increased
↓Decreased
↔No change

This section shows how diagnostic tests can be used in differential diagnosis and difficult diagnostic challenges. Material is presented in tabular format, and contents are listed in alphabetical order by disease topic.

Abbreviations used throughout this section include the following:

  • N= Normal
  • Abn = Abnormal
  • Pos = Positive
  • Neg = Negative
  • ↑ = Increased or high
  • ↓ = Decreased or low
  • Occ = Occasional

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Table 8–1. Acid–Base Disturbance: Laboratory Characteristics of Primary or Single Acid–Base Disturbance

Disturbance

Acute Primary Change

Partial Compensatory Response

Arterial pH

Serum [K+] (meq/L)

Unmeasured Anions (Anion Gap1)

Clinical Features

Normal

None

None

7.35–7.45

3.5–5.0

12–18

None

Respiratory acidosis

Pco2 ↑ (co2 retention)

↑ Hco3–

↓

↑

N

Dyspnea, polypnea, respiratory outflow obstruction, ↑ anterior-posterior chest diameter, rales, wheezes. In severe cases, stupor, disorientation, coma.

Respiratory alkalosis

Pco2 ↓ (co2 depletion)

↓ Hco3–

↑

↓

N or ↓

Anxiety, occasional complaint of breathlessness, frequent sighing, lungs usually clear to examination, positive Chvostek and Trousseau signs.

Metabolic acidosis

Hco3− depletion

↓ Pco2

↓

↑ or ↓

N or ↑

Weakness, air hunger, Kussmaul respiration, dry skin and mucous membranes, poor skin turgor. In severe cases, coma, hypotension, death.

Metabolic alkalosis

Hco3−

retention

↑ Pco2

↑

↓

N

Weakness, positive Chvostek and Trousseau signs, hyporeflexia.

1Anion gap = ([Na+] + [K+]) − (Hco3− + [CI−]) = 12–18 meq/L normally.

Reproduced, with permission, from Stobo JD et al (editors). The Principles and Practice of Medicine, 23rd ed. Originally published by Appleton & Lange. Copyright © ...

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