Page 2617 - Hematology_ Basic Principles and Practice ( PDFDrive )

2330 Part XIII Consultative Hematology

CLINICAL MANIFESTATIONS DIFFERENTIAL DIAGNOSIS

In the industrialized countries, the detection of cytopenias is It is important to distinguish true and clinically important findings
often encountered after routine laboratory testing or accompanies from false or transiently low values by having serial blood counts and/
minor or nonspecific symptoms. Especially for anemia, one may or a review of the peripheral smear.
not be able to disentangle anemia symptoms from other condi- In addition to causes delineated in Table 161.3, other causes
tions that coexist or underlie the anemia (e.g., rheumatoid arthritis). specific for anemia in older adults include unexplained iron deficiency/
Although fatigue may be the most obvious symptom of anemia, blood loss, hemolysis, and androgen deprivation.
the potential signs and symptoms are protean. Patients frequently
attribute fatigue to “growing old.” Observational studies demon-
strate a clear association between mild hemoglobin reduction (e.g., PROGNOSIS
less than 14 g/dL for women and less than 15 g/dL for men) and
reduced quality of life, strength, and mobility. Signs and symptoms The underlying condition driving the hematologic abnormality
may also direct one toward a cause, such as a pica suggesting iron usually dictates prognosis. Even a mildly low hemoglobin concentra-
deficiency or weight loss directing the clinician toward a systemic tion is an independent adverse prognostic factor in older adult
illness. patients, even in those 85 years and older.
Specific hemoglobin thresholds do not permit one to validate
symptoms because patients have different levels of reserve and organ
function, pace of hemoglobin fall, and underlying causes for the THERAPY
anemia. A more rapid pace of hemoglobin decline is at least as
important in provoking symptoms relative to anemia severity. To the extent possible, the underlying illness should be treated.
Particularly for anemia, the cause often remains obscure or the
underlying illness may not be amenable to therapy. We favor diag-
Neutropenia and Thrombocytopenia nostic and therapeutic trials of iron or vitamins for a defined period
of 3 months and discontinuing if ineffective. We reserve intravenous
Because of immune alterations associated with aging, one expects iron for severe anemia to avoid red blood cell transfusions or after
older adults at a given degree of neutropenia to suffer more infections clear failure of an adequate oral iron trial. One must be attuned to
and/or more serious infections. For example, not only do older adults fluctuations, normal variation, or confounding factors in assessing
have a greater probability of developing neutropenia, they also have response. For example, anemia following hospitalization may reflect
20
a heightened risk for life-threatening complications. Thrombocyto- phlebotomy, dilution, and an acute inflammatory response. The
penia in older adults increases bleeding risks compared with younger anemia may improve over months following hospitalization without
adults, best illustrated in chronic autoimmune thrombocytopenic therapy.
purpura. 21,22 For unexplained anemia, caution should be exercised in employ-
ing erythropoiesis-stimulating agents because of concerns for toxicity.
Polypharmacy remains a frequent problem in older adults and may
LABORATORY MANIFESTATIONS either cause hematologic abnormalities or adversely interact with the
detected blood abnormality. The primary physician, once prompted,
Diagnosis may determine many medications are unnecessary and can simply be
discontinued.
The use of age-adjusted norms remains quite controversial, because For older adults with an established hematologic malignancy for
normal aging itself has only a small impact on normal values. For which aggressive therapy may be entertained, a detailed assessment
cytopenias, blood counts are mandatory for diagnosis, to establish may guide decision-making (see box on Assessment of Older Adults
severity, and to guide the etiologic evaluation. For anemia, we advo- With Hematologic Malignancies).
cate applying the hemoglobin thresholds provided in Table 161.1.
Thresholds to define neutropenia and thrombocytopenia should not
differ from younger adults. FUTURE DIRECTIONS

The biology of aging is increasingly being better understood and
Laboratory Evaluation for Anemia may allow recognition of those at risk prior to overt malignancy.
Although interventional trials among older persons remain challeng-
See box on Evaluating Anemia in Older Adults. Review of the blood ing, the growing number of older and often relatively healthy adults
smear can be enormously useful, if not simply to exclude a high-risk mandates efforts to study older adults to define standards of clinical
hematologic disorder. practice.

Bone Marrow Evaluation
TABLE Differential Diagnosis for Common Causes of
Although a bone marrow examination may be invaluable in excluding 161.3 Cytopenias in Older Adults
serious marrow-related conditions, all cytopenias in older adults do
not warrant a bone marrow examination. We favor delaying bone Cytopenia of one or more lineages
marrow examination until recovery from acute events unless a high- Hematologic neoplasm
grade hematologic malignancy that would warrant immediate treat- Vitamin B 12 deficiency
ment is suspected. Mild fluctuations of counts, particularly within Autoimmune disorder
the range found over years, without other evidence of a hematologic Consumptive coagulopathy
malignancy may allow one to safely defer a bone marrow examina- Systemic inflammation
tion. Metaphase cytogenetics and whole-exome sequencing muta- Alcohol
tional panels are routinely performed. Specific fluorescence in situ Splenomegaly
hybridization (FISH) panels can be considered based on the level of Thyroid dysfunction
suspicion of a hematological malignancy. Human immunodeficiency virus