Hereditary Pelger-Huet Change

Blood Cell Identification – Graded
Case History
Blood smear comes from one of a pair of 34-year-old twin sisters, both of whom have a rheumatologic
condition consistent with systemic sclerosis. The CBC shows WBC = 4.0 x 10 9 /L, HGB = 13.2 g/dL,
HCT = 40%, and PLT = 210 x10 9 /L.
BCK/BCP-01
BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Neutrophil with Pelger-Huët
nucleus (acquired or
congenital)
Neutrophil, segmented or
band
23 100.0 1903 96.0 2688 91.8 Good
- - 67 3.4 228 7.9 Unacceptable
The arrow designates a neutrophil with bilobed nuclei (two round lobes connected by a delicate thin
filament) as seen in Pelger-Huët cells or neutrophils with Pelger-Huët nuclei. The neutrophil is mature
with nuclear chromatin that is typically denser than that seen in normal neutrophils, and the cytoplasm
is normally granulated. These findings are characteristic of the inherited autosomal dominant condition
known as Pelger-Huët anomaly. For this graded challenge 100.0% of referees and 93.5% of
participants chose this identification. In contrast with other conditions that may mimic these findings,
in the Pelger-Huët anomaly virtually all of the neutrophils contain bilobed nuclei. Unilobed nuclei in
mature neutrophils may be seen in individuals with homozygous Pelger-Huët genes.
Morphologic mimics of Pelger-Huet anomaly are well described, but in these other disorders only a
proportion of nuclei within neutrophils are affected (so-called pseudo-Pelger-Huët cells). Mimics of this
disorder include myelodysplastic syndrome, certain drug therapies, specific infections and other myeloid
malignancies.
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Blood Cell Identification – Graded
BCK/BCP-02
BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Eosinophil, any stage 23 95.0 1185 59.9 2879 99.0 Good
Neutrophil, segmented or
band
Neutrophil with Pelger-Huët
nucleus (acquired or
congenital)
1 5.0 398 20.1 10 0.3 Unacceptable*
- - 287 14.5 9 0.3 Unacceptable
The arrow designates an eosinophil that lies adjacent to a neutrophil with Pelger-Huet nucleus. The
eosinophil was correctly identified by 95.0% of referees and 83.2% of BCK and BCP total participants.
While both cells are of a similar size, the smaller pale salmon-colored specific granules of the neutrophil
contrast with the distinctive uniform coarse orange-red granules of the eosinophil.
In analyzing participant results, the Scientific Committee noted that BCK participants had a poorer
performance (59.9%) compared to BCP participants (99.0%) in identifying the arrowed cell as an
eosinophil. On review, slight color differences were noted between the Photomicrograph versus the
Photopage for this graded challenge. *Hence, the Scientific Committee has decided that both
“Neutrophil, segmented or band” and “Neutrophil with Pelger-Huet nucleus” are acceptable answers for
BCK participants only (code 30 = Scientific Committee Decision). Participants using photomicrographs
are reminded to view images using a slide projector in a darkened room or an illuminated, magnifying
hand-held viewer.
The majority of participants now subscribe to the CAP’s color photograph products for Blood Cell
Identification. With the increasing use of digital imagery and the advancements of color enhancing
technology, it is recommended that you consider enrolling in these products. The CAP’s color
photograph products offer you larger images for more accurate resulting as well as a supplementary
CD-ROM, giving you the ability to digitally project and view the images in greater detail. Please refer to
the 2008 Surveys catalog for more information.
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Blood Cell Identification – Graded
BCK/BCP-03
4
BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Basophil, any stage 23 100.0 1972 99.5 2895 99.6 Good
The arrow designates a basophil as correctly identified by 100.0% of referees and 99.6% of
participants. All basophils are characterized by a moderate number of densely stained coarse granules
of varying sizes and shapes. These granules appear larger than neutrophilic granules and often obscure
the nucleus. An uneven distribution of granules or partial degranulation may be observed (not seen in
this particular basophil). Depending on the Wright stain preparation, the granules may appear purple,
red or a deep blue-black.

Blood Cell Identification – Graded
BCK/BCP-04
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BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Lymphocyte 23 95.0 1790 90.3 2696 92.8 Good
Plasma cell, morphologically
mature
Lymphocyte, reactive (to
include plasmacytoid and
immunoblastic forms)
nRBC, normal or abnormal
morphology (blood only)
1 5.0 2 0.1 5 0.2 Unacceptable
- - 100 5.0 85 2.9 Unacceptable
- - 78 3.9 104 3.6 Unacceptable
The arrow designates a lymphocyte as correctly identified by 95.0% of referees and 91.8% of
participants. The lymphocyte is small in size with a scant amount of pale basophilic cytoplasm lacking
granules. The nuclear:cytoplasmic ratio is high, and the cell is largely occupied by the oval nucleus
containing diffusely dense chromatin.

Blood Cell Identification – Graded
BCK/BCP-05
6
BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Ovalocyte 23 100.0 1968 99.2 2882 99.2 Good
The two arrows in this low-power view designate ovalocytes, as was correctly identified by 100.0% of
referees and 99.2% of participants. Ovalocytes or elliptocytes are erythrocytes with blunt ends and
parallel sides. The blood smears of normal individuals frequently contain small numbers of
ovalocytes/elliptocytes. Hereditary ovalocytosis/elliptocytosis, however, will show a marked
ovalocytosis in which more than 25% of erythrocytes are affected.

Discussion
Originally described in 1928 by Pelger and first recognized as an autosomal dominant trait in 1931 by Huët,
the Pelger-Huët anomaly is characterized by abnormal neutrophil nuclear segmentation and extremely
coarse nuclear chromatin. In heterozygotes, this manifests as bilobed round nuclei connected by a thin
filament as shown in the case above, whereas unilobed neutrophil nuclei are predominantly seen in
homozygotes. Well known to hematopathologists and hematologists, this anomaly is generally easily
recognized as virtually all neutrophils show these changes. Neutrophil function is normal in individuals with
congenital Pelger-Huët anomaly. Recently, lamin B receptor mutations have been described in congenital
Pelger-Huët anomaly.
Acquired Pelger-Huët anomaly shares morphologic features resembling congenital Pelger-Huët anomaly, but
only a proportion of neutrophils are affected. Additional clinical history and the extent of these morphologic
features help clarify the etiology of these changes. Mimics of the Pelger-Huët anomaly are most frequently
found in myeloid malignancies (e.g. myelodysplastic syndrome and acute myeloid leukemia), but have also
been described in association with certain drugs, infections, and malignancies, among others. Neutrophil
function may be abnormal in some patients with myeloid malignancies.
Dysplastic changes in the peripheral blood of patients with myelodysplastic syndrome may be seen in white
blood cells, platelets and/or erythrocytes. Morphologic findings in white cells include abnormal cytoplasmic
granules, hypercondensed nuclear chromatin, and abnormal nuclear segmentation. Abnormal granulation
includes hypogranular neutrophils, neutrophils with so-called toxic granulations and Dohle bodies or
abnormally large granules. Changes in nuclear chromatin may show a typical hypercondensed pattern,
visible in myeloid series cells, as well as lymphocytes. Abnormal nuclear segmentation, including
hyposegmented and hypersegmented forms are also well described.
Acquired Pelger-Huët anomaly has been described in association with certain antibiotics, chemotherapeutic
agents, and immunosuppressive medications. The latter medications are used in transplant recipients and
include mycophenolate mofetil (MMF), tacrolimus, and ganciclovir. The neutrophil abnormalities are
reversible following discontinuation or reduction of medications.
References:
1. Constantino BT. Pelger-Huët anomaly—morphology, mechanism, and significance in the peripheral blood
film. Lab Med 2005;36:103-107.
2. Etzell JE, Wang E. Acquired Pelger-Huët anomaly in association with concomitant tacrolimus and
mycophenolate mofetil in a liver transplant patient. Arch Pathol Lab Med 2006;130:93-96.
3. Hoffman K, Dreger CK, Olins AL, et al. Mutations in the gene encoding the lamin B receptor produce an
altered nuclear morphology in granulocytes (Pelger-Huët anomaly). Nat Genet 2002;31:410-414.
4. Skendzel LP, Hoffman GC. The Pelger anomaly of leukocytes: forty-one cases in seven families. Am J
Clin Pathol 1962; 37:294-301.
5. Skubitz K. Qualitative disorders of leukocytes. In: Greer JP, Foerster J, Lukens JN, Rodgers GM,
Paraskevas F, Glader B, eds. Wintrobe’s Clinical Hematology. 11th ed. Philadelphia, Pa: Lippincott Williams
& Wilkins; 2004; 1802-1803.
Tracy I George, MD, Vice-Chair
Hematology and Clinical Microscopy Resource Committee
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Blood Cell Identification – Ungraded
Case History
Blood smear is from a 48-year-old female with a history of small bowel obstruction and enterocutaneous
fistula. CBC data include: WBC = 35.2 x 10 9 /L, RBC = 2.87 x 10 12 /L, HGB = 8.8 g/dL, HCT = 25.5%,
MCV = 89 fL, MCH = 30.1 pg, MCHC = 33.8 g/dL, RDW 14.6%, PLT = 230 x 10 9 /L. Differential results
are as follows: Neutrophils = 96%; Lymphocytes = 2%; Monocytes = 1%; Eosinophils = 0%;
Basophils = 1%.
BCK/BCP-06
BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Leukocyte with phagocytized
fungi
Macrophage with
phagocytized fungi,
leishmania, or toxoplasma
16 94.0 1472 77.6 2228 80.3 Educational
1 6.0 369 19.5 455 16.4 Educational
All four images demonstrate leukocytes with phagocytized fungi. These leukocytes with phagocytized
fungi were correctly identified by 94.0% of the referees and 79.2% of the participants. Six percent of
the referees and 17.6 % of the participants identified macrophage with phagocytized fungi, leishmania
or toxoplasma". As macrophages are seen in the bone marrow, identifying this cell as a macrophage is
not the best choice. The yeast are round to oval. Fungi are only rarely seen in the peripheral blood and
usually the number of organisms is few. Intracellular fungi may be confused with precipitated stain
overlying a leukocyte, large toxic granules, Dohle bodies or large bacterial cocci.
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Blood Cell Identification – Ungraded
BCK/BCP-07
BCK/BCP-08
BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Fungi, extracellular 16 94.0 1805 95.3 2631 94.7 Educational
Neutrophil necrobiosis
(degenerated neutrophil)
1 6.0 40 2.1 87 3.1 Educational
Extracellular fungi, as seen in this peripheral blood smear, can be seen in patients with severe
disseminated infection or as a possible contaminant. Finding intracellular fungi supports the diagnosis of
disseminated infection. The extracellular fungi were correctly identified by 94.0% of the referees and
94.9% of the participants.
BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Eosinophil, any stage 17 100.0 1896 99.6 2770 99.0 Educational
This classic eosinophil has a bilobed nucleus and abundant coarse, orange-red granules of uniform size.
Eosinophils have a classic appearance and were correctly identified by 100.0% of the referees and
99.2% of the participants.
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Blood Cell Identification – Ungraded
BCK/BCP-09
10
BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Basophil, any stage 17 100.0 1820 95.6 2727 97.5 Educational
Basophils are recognized by the densely stained granules of varying sizes and shape, which most
frequently stain blue-black. Basophils have a classic appearance and were correctly identified by
100.0% of the referees and 96.8% of the participants.

Blood Cell Identification – Ungraded
BCK/BCP-10
11
BCK BCP
Referees Participants Participants Performance
Identification No. % No. % No. % Evaluation
Neutrophil, toxic (to include
toxic granulation and/or Dohle
bodies, and/or toxic
vacuolization)
Neutrophil necrobiosis
(degenerated neutrophil)
17 100.0 1785 93.7 2654 94.9 Educational
- - 99 5.2 71 2.5 Educational
The neutrophils in this image exhibit toxic changes with prominent cytoplasmic vacuoles in the two
cells marked with the arrows. The third cell in the image has another commonly seen toxic change,
namely, toxic granulation. Toxic changes in neutrophils are present in many clinical situations, with
cytoplasmic vacuolation most associated with sepsis, as seen in this patient. Toxic neutrophils were
correctly identified by 100.0% of the referees and 94.4% of the participants.

Discussion
The CBC results and the peripheral blood smear images from this 48-year-old female with an
enterocutaneous fistula demonstrate disseminated candidiasis. In BCK/BCP-06, all four photos are
leukocytes with phagocytized fungi. The yeast forms are round to oval and have a pseudo-halo surrounding
them. As is not uncommonly seen in sepsis, the leukocytes exhibit reactive changes, to include cytoplasmic
vacuoles, as shown here. Image BCK/BCP-07 has extracellular fungi. When extracellular fungi are found in
the peripheral blood they are usually associated with intracellular organisms. These findings indicate a
serious systemic infection.
Systemic candidiasis is the fourth most common cause of nosocomial bloodstream infections. Over the past
20 years the number of blood stream infections related to Candida species has risen 5- to 10-fold. There is
a significant associated morbidity and mortality with systemic infection, with some studies reporting the
mortality as high as 40.0%. Approximately two-thirds of the cases are due to Candida albicans and the
remainder to non-albicans species. Candida glabrata in older patients and Candida parapsilosis in the
neonatal and pediatric population comprise the majority of the non-albicans systemic infections.
Candida species form a part of the normal microbial flora of the mouth and gastrointestinal tract.
Transmission of Candida is almost exclusively endogenous, with rare cases of transmission from a health
care worker or medical equipment. Oropharyngeal infection and vulvovaginal infection are the most
commonly seen Candida infections. Neonates, neutropenic patients, hematopoietic stem cell and organ
transplant recipients and other immunocompromised patients are at higher risk for systemic Candida
infection. These patients present with fever and chills, which are unresponsive to antibacterial therapy.
Severe sepsis, septic shock and end-organ dysfunction (acute renal failure, altered mental status) can
develop quickly in these patients, even with appropriate therapy. Progression to septic shock is associated
with an overall higher mortality.
The diagnosis of systemic candidiasis is made with blood culture or culture of infected tissue. A gram stain
of blood cultures demonstrating the presence of pseudohyphae in clusters is helpful in distinguishing
Candida albicans from non-albicans. Drug resistance is rare. Testing for susceptibility to fluconazole,
itraconazole and flucytosine may be helpful, especially with infections due to non-albicans species.
A peripheral blood smear with neutrophilia, extracellular and intracellular fungi, as seen in this patient, is an
insensitive method for diagnosing systemic Candida infection. Detection of candidemia by peripheral blood
smear examination requires a yeast concentration of 1 to 5 X105 CFU/mL or greater. As positive blood
cultures take at least 2 days to turn positive, exploration of more rapid diagnostic methods is being
explored. Conventional PCR assays offer increased sensitivity, but more recent studies utilizing multiplex
real-time PCR show even greater promise. Multiplex real-time PCR requires a very small amount of blood or
tissue, detects many Candida species and provides a sensitive and specific result much quicker than
standard blood culture. Additional studies using this technology may help in earlier diagnosis and treatment.
Treatment of invasive candidiasis is with intravenous (IV) Amphotericin B or IV or oral Fluconazole. Hospital
surveillance, prophylaxis when indicated (patients with prolonged severe neutropenia or who receive a
solid-organ transplant) and better diagnostic tests may facilitate an earlier clinical diagnosis and improved
overall survival.
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References:
1. Bassetti M, Trecarichi EM, Righi E, et al. Incidence, risk factors and predictors of outcome of
candidemia. Survey in 2 Italian university hospitals. Diagn Microbiol Infect Dis 2007;58:325-331.
2. Branda, JA, Ferraro MJ, Kratz A. Sensitivity of peripheal blood smear review for the diagnosis of
Candida fungemia. Arch Pathol Lab Med 2007;131:97-101.
3. Candidiasis. www.cdc.gov
4. Gudlaugsson O, Gillespie S, Lee K, et al. Attibutable mortality of nosocomial candidemia, revisited. Clin
InfectDis 2003;37:1172-1177.
4. Harrington A, McCourtney K, Nowowiejski D, Limaye A. Differentiation of Candida albicans from nonalbicans
yeast directly from blood cultures by Gram stain morphology. Eur J Clin Microbiol Infect Dis
2007;26:325-329.
5. Innings A, Ullberg M, Johansson A, et al. Multiplex real-time PCR targeting the RNase P RNA gene for
detection and identification of Candida species in blood. J Clin Micro 2007;45:874-880.
6. Pfaller MA, Diekema DJ. Role of sentinel surveillance of candidemia: trends in species distribution and
antifungal susceptibility. J Clin Micro 2002; 40:3551-3557.
7. Rex JH, Walsh TJ, Sobel JD, et al. Practice guidelines for the treatment of candidiasis. Infectious
Diseases Society of America. Clin Infect Dis 2000;30:662-678.
8. Wisplinghoff H, Seifert H, Wenzel RP, Edmond MB. Inflammatory response and clinical course of adult
patients with nosocomial bloodstream infections caused by Candida spp. Clin Microbiol Infect
2006;12:170-177.
Deborah A. Perry, MD
Hematology and Clinical Microscopy Resource Committee
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