Hematologic and cytofluorographic analysis of patients with feltyaposs syndrome a hypothesis that a discrete event leads to large granular lymphocyte expansions in this condition.

ARTHRITIS & RHEUMATISM
Vol. 38, No.9, September 1995, pp 1252-1259
0 1995, American College of Rheumatology
1252
HEMATOLOGIC AND CYTOFLUOROGRAPHIC ANALYSIS OF
PATIENTS WITH FELTY’S SYNDROME
A Hypothesis that a Discrete Event Leads to Large Granular Lymphocyte
Expansions in this Condition
S. J. BOWMAN, V. CORRIGALL, G. S. PANAYI, and J. S. LANCHBURY
Objective. To compare hematologic and cytofluorographic features in Felty’s syndrome (FS) patients
with and without the large granular lymphocyte (LGL)
syndrome.
Methods. Peripheral blood cells from FS patients
and from 2 control groups (rheumatoid arthritis [RA]
patients and subjects without symptoms of a rheumatic
disease) were analyzed by hematologic and cytofluorographic techniques. A separate assessment of disease
activity was performed.
Results. FS patients had reduced lymphocyte and
platelet counts, with a parallel reduction in lymphocyte
subsets examined. CD4 counts were reduced in all FS
patients, including those with the LGL syndrome. Disease activity was lower in FS patients than in RA control
patients. Treatment was similar in all patient groups.
No direct association was seen between LGL numbers
and duration of RA or neutrophil counts in RA groups.
Conclusion. Hematologic abnormalities in FS extend beyond neutropenia. Although similarities were
seen between FS patients and FS patients with the LGL
syndrome (e.g., CD4 lymphopenia), evidence for a
gradation from FS to the LGL syndrome was not seen,
thus favoring the hypothesis that a “transforming
event” is required.
Felty’s syndrome (FS), which comprises rheumatoid arthritis (RA), leukopenia, and often splenomegaly (l), occurs in -1% of RA patients. Between
15% and 40% of FS patients also have a form of T cell
“leukemia,” the large granular lymphocyte (LGL)
syndrome (2-4). In this latter syndrome, there is an
expansion of peripheral blood T lymphocytes that
have a large granular morphology. Conversely, a number of studies have estimated that up to 30% of
patients with the T cell LGL syndrome have evidence
of RA (5). LGLs comprise -15% of normal peripheral
blood lymphocytes, although they increase in number
with age (6). LGLs include natural killer (NK) cells as
well as T cells, which are of interest in the present
study. The most common surface phenotype of T cell
LGLs in FS patients is CD3+,CD8+,CD57+,
CD16+/-. CD56, a marker seen on NK cells, is less
commonly expressed on T cell LGLs.
This study was directed toward identifying hematologic features and lymphocyte subsets in patients
with FS, with or without the LGL syndrome, in RA
control patients, and in a group of control subjects
without symptoms of rheumatic diseases, to give further insight into the pathogenesis of these conditions.
PATIENTS AND METHODS
Supported in part by the Arthritis and Rheumatism Council,
UK. Dr. Bowman’s work was supported by an MRC Training
Fellowship.
S . J. Bowman, MRCP, V. Comgall, PhD, G. S. Panayi,
FRCP, J. S. Lanchbury, PhD: UMDS, Guy’s Hospital, London,
UK.
Address reprint requests to J. S. Lanchbury, PhD, Division
of Medicine, UMDS, Guy’s Hospital, London SE1 9RT, UK.
Submittted for publication December 2, 1994;accepted in
revised form March 20, 1995.
Patient population. Fifty-five FS patients were recruited for this study. All fulfilled the American College of
Rheumatology (formerly, the American Rheumatism Association) 1987 criteria for RA (7). In addition, they all had a
current or previous history of an unexplained neutropenia
(neutrophil count below 2 x 10’Aiter) that persisted for at
least 6 months. Splenomegaly was not an essential criterion
for the diagnosis of FS in this study, a guideline that is now
generally accepted (1). All patients were Northern European
1253
HEMATOLOGY OF FS AND LGL SYNDROME
Caucasoids except for 1 patient, who was of Turkish Cypriot
origin. These patients are described in detail elsewhere (4).
Briefly, 17 of them had evidence of the LGL syndrome, while 32 did not. The remaining 6 patients could not
be categorized into either group and were excluded from
further study. The LGL syndrome was defined as either an
absolute lymphocytosis of LGLs above 1 X 10’hiter or an
increased percentage of LGLs of at least 25% of the total
lymphocytes, persisting for at least 6 months. LGLs were
identified by morphology and immunophenotyping, and 15 of
17 had evidence of clonal disease based on restriction
fragment length polymorphism (RFLP) or sequencing analysis (4).
Control population. Two control groups were studied. Since the number of LGLs increases with age (6), it was
important to ensure that subjects in the control groups had
the same age range as those in the FS groups. The first
control group was an outpatient group of 23 randomly
recruited RA patients attending Guy’s Hospital outpatient
clinics. The second was a group of individuals without
rheumatic disease symptoms (non-rheumatic disease [NRD]
controls). This comprised both hospital staff members and
individuals attending outpatient clinics at Guy’s Hospital for
followup of routine medical conditions such as hypertension.
All were Northern European Caucasoids, except for 2 of the
RA patients (1 Greek Cypriot, 1 Asian) and 1 of the NRD
controls (Greek Cypriot).
Cell separation, immunofluorescence, and flow cytometry. Venous peripheral blood was collected into tubes
containing preservative-free heparin, and mononuclear cells
were separated on a Lymphoprep (Nycomed, Oslo, Norway) density gradient. Immunophenotyping was performed
by flow cytometry (fluorescence-activated cell sorter
[FACS] analysis) using a Becton Dickinson FACScan (Oxford, UK). Double staining was performed using the following phycoerythrin- and fluorescein isothiocyanate (FITCt
conjugated monoclonal antibodies: mouse IgGl antibodies
as negative controls, anti-CD3, anti-CD4, anti-CD8, antiCD16, anti-CD56, anti-CD57, anti-T cell receptor alp and
ylS, and FITC-conjugated goat anti-mouse antibodies (all
from Becton Dickinson). Standard complete blood cell
counts and white blood cell differential counts were used to
calculate absolute numbers of each lymphocyte subset.
Disease activity. The European League Against
Rheumatism (EULAR) core data set (8) was used to assess
RA activity in a proportion of the FS patients and RA
controls. This comprised the number of swollen joints (28
joint count), number of tender joints (28 joint count), joint
pain (10-cm visual analog scale [VAS]), patient’s global
assessment of disease activity (10-cm VAS), duration of
morning stiffness (minutes), and the erythrocyte sedimentation rate (ESR).
In addition, a modified disease activity score (DAS)
(9) was calculated according to the following formula: DAS =
(0.555 x d n tender joints) + (0.284 x d n swollen joints) +
(0.7 X In ESR) + (0.0142 x patient’s global assessment), where
the maximum “n” value is 28.
Statistical analysis. The Mann-Whitney U test and
chi-square test were used to compare results between
groups. P < 0.05 was considered significant. For correla-
tions between variables, Spearman’s rank coefficient of
correlation was used.
RESULTS
Clinical features. Table 1 shows the comparison
of basic clinical data among the 4 groups. The salient
features are as follows. The LGL group was older than
the other groups and had developed neutropenia at an
older age. The mean time period between the development of RA and the development of FS was 12 years
in the FS group and 15 years in the LGL group, but
with enormous variation from patient to patient. The
female-to-male ratio in the FS and LGL patients was
less than that in the RA patients. Thirteen of the 32 FS
patients (41%) and 2 of the 17 LGL patients (12%)
currently had a neutrophil count above 2 x 10’Aiter
(both LGL patients had clonal LGL expansions by
RFLP analysis [4]). Splenomegaly was more common
in the FS patients than in the LGL patients.
All patient groups had a high incidence of
seropositivity for rheumatoid factor and erosive disease. Approximately one-third of the FS and LGL
patients had a history of infections. Most of those
whose bone marrow had been analyzed had an active
marrow, with only 2 of 18 FS patients (11%) having
decreased granulopoiesis. Four of 11 LGL patients
(36%) and 3 of 18 FS patients (17%) had bone marrow
lymphocytosis. Analysis of the peripheral blood from
the 3 FS patients showed no evidence of the LGL
syndrome. Drug treatment in the FS, LGL, and RA
patient groups was similar.
Complete blood cell count parameters. By definition, the FS and LGL groups had a significantly
reduced neutrophil count compared with the control
groups (Table 2). In the FS group, the lymphocyte and
platelet counts were also reduced, which was not seen
in the LGL group. The red blood cell count was not
affected in either the FS or the LGL group.
The RA patient controls also differed from the
NRD controls. The neutrophil and platelet counts
were significantly increased, and the hemoglobin reduced. This is all suggestive of active inflammatory
disease. The mean ESR in these patients was also
substantially increased at 47 mm/hour, with an ipterquartile range of 32-58 mm/hour, which would be
compatible with active inflammation. Three RA patients were lymphopenic (lymphocyte count below l x
10’Aiter; interquartile range 0.83-0.98 X lO’Aiter), as
was 1 individual from the NRD control group (0.91 X
1O’Aiter).
BOWMAN ET AL
1254
Table 1. Clinical features of the study groups*
RA patients NRD controls LGL patients
(n = 17)
(n = 23)
(n = 20)
FS patients
(n = 32)
~
Age-Females:males, n (ratio)
RA duration, mean f SD years
Age at RA onset, mean f SD years
FS duration, mean f SD years
Age at FS onset, mean f SD years
RA-FS period, mean t SD years
Neutrophils now >2 x lO’Iliter, n (%)
Splenomegaly, n (%)
RF positive by latex test, n (%)
Radiographic erosions, n (%)
Infections, n (%)
Bone marrow, dtotal tested
Active
Lymphocytosis
Decreased granulocytes
Current treatment, n
Prednisolone f DMARD
DMARD 2 NSAID
NSAID alone
6 0 f 127
14:18 (0.8)
17 f 11
43 f 14
4 f 5
56 f 126
12 f 11
13 (4117
28/32 (88)#
28/32 (88)
23/19 (79)
9/32 (28)
63 f 11$
17:6 (2.8)
15 -+ 8
48 & 13
NA
NA
NA
23 (100)
NK
19/23 (83)
11/13 (85)
NK
60 f 21
13:7 (1.9)
NA
NA
NA
NA
NA
20 (100)
NK
NK
NA
NK
71 t 10
10:7 (1.4)
20 f 15
50 f 18
5 f 5
66 f 12
15 f 13
2 (12)
9/17 (53)
14/17 (82)
9/16 (56)
6/17 (35)
14/18
3/18
2/18
NK
NK
NK
NK
NK
NK
11111
411 1
0111
11
9
12
8
9
6
NA
NA
NA
10
3
4
* P values determined by Mann-Whitney U test (for continuous data) or by chi-square with Yates’
correction (for discontinuous data). See Patients and Methods for definitions of the study groups. FS
= Felty’s syndrome; RA = rheumatoid arthritis; NRD = non-rheumatic disease; LGL = large
granular lymphocyte syndrome; NA = not applicable; NK = not known; RF = rheumatoid factor;
DMARD = disease-modifying antirheumatic drug; NSAID = nonsteroidal antiinflammatory drug.
t P = 0.004 versus LGL group.
$ P = 0.03 versus LGL group.
1 P = 0.009 versus LGL group.
ll P = 0.05 versus LGL group.
# P = 0.02 versus LGL group.
reduction in CD8 counts (0.22 ? 0.13 X lO’/liter),
while in the LGL group it was increased (2.60 2.55
x lO’/liter). The RA group had a borderline reduction
in CD8 cells (0.29 ? 0.23 x 109/liter)compared with the
NRD control group (0.39 ? 0.24 x l@/liter) (P= 0.046).
Examination of the CD4:CD8 ratio is instructive. In the LGL group, the ratio was grossly abnormal
FACS analysis of peripheral blood lymphocyte
phenotype. The CD3 count in the FS group (mean ?
SD 0.67 0.36 x 10’hiter) was significantly reduced
compared with the counts in the other groups (Table
3). The CD4 count was reduced in both the FS group
(0.40 0.24 x 10’hiter) and the LGL group (0.41 ?
0.38 X lO’/liter). In the FS group, there was a similar
*
*
*
Table 2. Hematologic data on the study groups*
Neutrophils, x 10’Iliter
Lymphocytes, xlO9/Iiter
Platelets, x lo’fliter
Hemoglobin, g d d l
FS patients
(n = 32)
RA patients
(n = 23)
NRD controls
(n = 20)
LGL patients
(n = 17)
1.89 f 1.647
0.99 f 0.42$
155 f 771
12.6 f 1.4
6.12 f 1.957
1.60 f 0.53
304 f 9571
12.1 f 1.2#
4.18 5 1.227
1.85 f 0.68
234 f 728
13.0 f 1.3
1.27 5 1.257
3.62 f 3.17
207 t 99
12.5 f 1.5
* The mean f SD erythrocyte sedimentation rate in the RA patients was 47 f 28 mdhour (range
5-130, interquartile range 32-58). Values are the mean f SD. See Table 1 and Patients and Methods
for definitions.
7 All groups differed significantly from all other groups at P = 0.0002, except for the FS group versus
the LGL group, which were not significantly different from each other.
$ P = 0.0003 versus all other groups.
1P = 0.006 versus all other groups, except the LGL group.
llP = 0.006 versus all other groups, including the LGL group.
# P = 0.02 versus NRD controls.
HEMATOLOGY OF FS AND LGL SYNDROME
1255
Table 3. Flow cytometry findings in the study groups*
RA patients
(n = 23)
NRD controls
(n = 20)
LGL patients
(n = 17)
1.06 f 0.35t
0.73 2 0.298
0.29 f 0.23#
3.6 f 2.3
0.24 f 0.20
20.9 2 14.1
0.013 f 0.018
0.070 -t 0.078##
1.31 f 0.66
0.84 f 0.439
0.39 f 0.24
2.5 f 1.3
0.24 f 0.16
19.2 f 13.3
0.021 f 0.023
0.117 2 0.074
3.25 -t 3.05
0.41 f 0.38
2.60 f 2.55**
0.3 & 0.3**
2.08 f 2.53**
57.0 f 20.9**
0.825 f 1.72289
0.163 f 0.360
FS patients
(n = 32)
0.67 f 0.36t
CD3 count, x 109/liter
CD4 count, x lphiter
0.40 f 0.249
CD8 count, X 10’hiter
0.22 f 0.13ll
CD4:CD8
2.2 f 1.4tt
CD3+,CD57+, xl@hter
0.12 f 0.09$$
CD57 +/CD3 + , %
18.9 & 11.0
CD3+,CD16+, X 109/Iiter 0.017 f 0.032
CD3+,CD56+, X lO’/Iiter 0.030 f 0.032Tll
* Values are the mean f SD. See Table 1 and Patients and Methods for definitions.
t P = O.OOO4 versus all other groups.
$ P = 0.014 versus LGL group.
9 P = O.ooO1-O.OOO8 for FS versus RA and NRD groups, for RA versus FS and LGL groups, and for
NRD versus LGL group.
ll P = 0.002 versus NRD group.
# P = 0.046 versus NRD group.
** P = O.OOO1 versus all other groups.
tt P = 0.008 versus RA group.
S$ P = 0.027 versus RA group and P = 0.007 versus NRD group.
98 P = 0.013 versus FS group and P = 0.031 versus RA group.
llllP = 0.001 versus RA and NRD groups.
## P = 0.01 versus NRD group.
(mean 2 SD 0.3 _t 0.3), as expected. The ratio in the
FS group (2.2 ? 1.4) was very similar to that in the
NRD control group (2.5 ? 1.3), suggestive of a parallel
reduction in CD4 and CD8 cells. In the RA patients
(3.6 ? 2.3), the CD4:CD8 ratio was increased, although not significantly, compared with the NRD
controls.
By definition, CD3+,CD57+ counts were significantly increased in the LGL group compared with
the other groups (2.08 -t 2.53 X 10’hiter; P = 0.0001).
However, while they were reduced in the FS group
compared with the levels in the RA and NRD control
groups, the percentage expression was unchanged,
again suggestive of a parallel decrease in all of the
lymphocyte subtypes examined (Figure 1). CD16
showed an increased expression in the LGL group
compared with the FS and RA groups, while CD56
expression was reduced in the FS and RA groups.
With age, the absolute lymphocyte count decreases, while the percentage of T cells that express
CD57 increases (6). One previous study of FS failed to
specify the age of the control group (3). In the present
study, NRD control samples came from both laboratory staff and outpatients undergoing routine followup
for conditions such as hypertension, which is commonly present in older individuals. There were no
significant differences between the 2 subgroups with
8
Figure 1. Comparison of hematologic and cytofluorographic features in 32 patients with Felty’s syndrome (FS) alone, by treatment
group. Group 1, FS pred+ = 11 patients taking oral prednisolone
(pred) with or without disease-modifying antirheumatic drugs
(DMARDs) or nonsteroidal antiinflammatory drugs (NSAIDs).
Group 2, FS DMARD = 9 patients taking DMARDs with or without
NSAIDs. Group 3, FS NSAID = 12 patients taking NSAIDs or no
antirheumatic treatment. * P = 0.025 group 2 versus group 3. The
values for age, rheumatoid arthritis (RA) duration, and FS duration
were divided by 10, and the platelet count by 100, in order to fit the
scale of the figure.
1256
BOWMAN ET AL
Table 4. Spearman correlation coefficients (r) for comparisons of CD57 expression as a percentage
of CD3+ cells (%), and CD57+,CD3+ absolute cell counts (count), with the variables specified, in the
study groups*
RA patients
r = 0.43t
(n = 23)
FS patients
r = 0.35t
(n = 32)
%
Age (years)
RA duration (years)
FS duration (years)
Neutrophils (Xl@Aiter)
0.38
0.16
0.02
-0.07
0.14
0.09
0.14
LGL patients
r = 0.51t
(n = 17)
%
Count
%
Count
%
Count
0.01
0.14
NA
-0.18
0.05
0.07
NA
-0.04
0.56
NA
NA
0.38
0.26
NA
NA
0.36
-0.01
-0.25
-0.07
0.39
0.22
-0.13
-0.13
0.19
Count
-0.25
NRD controls
r = 0.45t
(n = 20)
* See Table 1 and Patients and Methods for definitions.
t r value for P < 0.05, which is considered significant.
regard to any of the parameters analyzed except for
age (43.8 2 14.7 versus 76.3 t 10.8; P = 0.0004 by
Mann-Whitney U test) and, consequently, CD3+,
CD57+ expression (12.8 2 9.5% versus 25.6 +. 13.9%;
P = 0.0284 by Mann-Whitney U test).
Comparison between FS patients with current
neutropenia and those with a neutrophil count currently
above 2.0 x 109/liter. Comparison of the 19 FS patients
currently neutropenic with the 13 who were no longer
neutropenic found few significant differences. Clearly,
the neutrophil counts were different (0.89 +. 0.45
versus 3.34 2 1.64 x 10g/liter; P = O.OOO1 by MannWhitney U test). The duration of FS was also signifi3.38
cantly different between these groups (3.00
versus 6.31 2 5.92 years; P = 0.048 by Mann-Whitney
U test). The longer the duration of disease the more
likely the neutrophil count has had time to recover.
There were no significant differences between these
two groups with regard to any of the other laboratory
indices.
There was a significant sex difference in the
occurrence of neutropenia. Twelve of the 19 currently
neutropenic patients (63%) and 2 of the 13 of those
whose counts had recovered (15%) were males (P =
0.021 by chi-square test). Eighteen of the 19 currently
neutropenic patients (95%) were HLA-DR4 positive,
compared with 8 of the 13 non-neutropenic patients
(62%) (P= 0.057).
Treatment. One important issue with regard to
FS patients is whether treatment could account for
some or all of the abnormalities. We categorized the
patients according to 3 main treatment groups: 1)
patients taking oral steroids with or without other
treatments, such as disease-modifying antirheumatic
drugs (DMARDs) or nonsteroidal antiinflammatory
drugs (NSAIDs). 2) Patients taking a DMARD, with or
*
without an NSAID, but not taking oral steroids. 3)
Patients not taking oral steroids or a DMARD, but
might be taking an NSAID. The only significant difference was that patients in treatment group 3 were
older (67 2 9 years) than those in treatment group 2 (52
f 16 years) (P = 0.03 by Mann-Whitney U test)
(Figure 1).
Correlation of CD3+,CD57+ expression with
other variables in patient and control groups. In the
NRD control group, a correlation of increasing age
with the percentage of CD3 cells that coexpressed
CD57 was found (Spearman’s r = 0.56) (Table 4).
Absolute numbers of CD3-t ,CD57+ cells did not show
this correlation. There was a significant inverse correlation between age and total lymphocyte count (r =
-0.55) in the NRD controls. The findings in the FS
patients were similar to those in the NRD controls.
However, in the RA and the LGL patient groups, this
relationship was not seen. No correlation was seen
between the percentage expression of CD57 on CD3
cells and disease duration in any of the patient groups
(Table 4). No inverse relationship between the numbers of LGLs (as shown by CD3+,CD57+ cells) or
CD57/CD3% expression and the peripheral blood neutrophil count was seen in any of the groups studied
(Table 4).
Disease activity. A comparison of disease activity between 17 of the 49 FS patients (35%; 10 with FS
alone and 7 with FS and the LGL syndrome) and 14 of
the 23 RA patients (61%) showed that all activity
indices were lower in the FS patients than in the RA
patients, although these differences did not all reach
statistical significance (Table 5).
The modified DAS was significantly lower in
the FS group (P = 0.008). Numbers were insufficient
to analyze the FS patients with and without the LGL
HEMATOLOGY OF FS AND LGL SYNDROME
Table 5. Comparison of disease activity measurements in 17 FS
patients (10 with FS alone and 7 with FS and LGL syndrome) and 14
RA patients*
stiffness, minutes
Patient’s assessment of pain
(10-cm VAS)
Patient’s global assessment
(10-cm VAS)
No. of swollen joints
(maximum 28)
No. of tender joints
(maximum 28)
Erythrocyte sedimentation rate
(mmhour)
Modified Disease Activity Score
AM
FSLGL patients
(n = 17)
RA patients
44 f 62
3.0 f 1.8t
114 2 167
5.3 2 2.9
2.4 2 1.7$
4.7
3.5
6.4 f 6.5
f
4.0
3.2 2 3.8
(n = 14)
7.8
2
k
2.7
8.7
34 2 38
39 2 24
2.9 f 1.25
4.5 f 1.4
* Values are the mean 2 SD. VAS = visual analog scale. See Table
1 and Patients and Methods for other definitions.
= 0.037 versus RA group.
= 0.020 versus RA group.
5 P = 0.008 versus RA group (P = 0.006 for 10 patients with FS
alone versus RA group).
tP
tP
syndrome as separate groups. A comparison between
the 10 patients with FS alone and the 14 RA patients
yielded similar results, but with more of the indices
differing significantly (P = 0.006) (Table 5).
DISCUSSION
The term Felty’s syndrome is now used to
describe the association of RA with neutropenia
(1,lO). Although splenomegaly is common, it varies
over time and in extent, and it may be absent (1,lO).
We have provided evidence that hematologic abnormalities in FS extend beyond neutropenia, with parallel reductions in CD4 and CD8 cells. A detailed
comparison of the hematologic features and T lymphocyte subsets in FS patients with and without LGL
expansions, as well as in RA patients without neutropenia, has provided important clues to the relationship
between these conditions. Most importantly, evidence
of a gradation from FS to the LGL syndrome was not
seen, thus favoring the hypothesis that a “transforming event” is required.
The neutropenia in FS is variable. In some
patients it is profound, in others it fluctuates, and in a
proportion of patients it recovers completely (1,3,10).
In the present study, patients in this latter group were
more likely to be female and to have a lower frequency
of HLA-DR4. As an explanation for this difference,
we cannot exclude the theoretical possibility that
HLA-DR4 positive male patients die early in the
1257
course of FS. The recovery may occur after a long
period of neutropenia. One of the patients described in
our study, for example, has a severe seropositive,
erosive, destructive arthropathy (now quiescent),
splenomegaly, and is positive for HLA-DR4. She had
a profound neutropenia, with a nadir of 0.1 X lO’Aiter,
over an 8-year period, which resolved spontaneously.
Although neutropenia is the most prominent
feature, FS is a more generalized disease that may
affect other cell types. Anemia, lymphopenia, and
thrombocytopenia have all been described (10) to
various extents (1). It has been suggested that one
reason for these findings is hypersplenism. In this
study, however, the presence of splenomegaly was not
related to the levels of these cell types in the blood,
and the red blood cell count was undected, which is
unusual for hypersplenism.
Although it is clear that the incidence of infection in FS patients is, in general, related to the degree
of neutropenia (1l), this is by no means absolute, and
the low CD4 count may be an additional contributing
factor. Patients with FS and LGL expansions also had
low CD4 counts, and this may imply that there are
further similarities in the pathogenic mechanisms of
these 2 variants of FS. CD3+,CD16+ cells, and to a
lesser extent CD3+,CD56+ cells, were higher in the
LGL group, but there was enormous variation from
patient to patient, since individual LGL expansions
either expressed or did not express these markers.
They were also reduced in parallel with the other
lymphocyte subsets in the FS patients. The possibility
that antiarthritic drugs could account for these variations was also examined (Figure 1). No difference was
found between FS patients grouped with regard to
antirheumatic treatment, except that DMARDs were
less common in older patients. This may reflect a
“bum-out” of the disease in the older patients, or it
may mean that the physician prefers less-aggressive
therapy in this group. It is clear, however, that oral
steroid use cannot account for the abnormalities seen
in the FS patients, and although DMARDs appear to
be effective treatment for the neutropenia, there is
little evidence that steroids are of any benefit (1).
One hypothesis for the presence of LGL expansions in patients with FS is that they represent a
spectrum of disease with a potential for progression
over time, from FS to FS with the LGL syndrome.
The FS group as a whole might have been expected to
show some sign of this with a relative increase in
CD3+,CD8+,CD57+ cells. This was not found. The
FACS analysis demonstrated that FS patients had a
1258
parallel reduction in all of the lymphocyte subsets
demonstrated. There was no relative preservation of
CD3+,CD57+ cells to suggest a “low level” LGL
syndrome. That is, rather than a complete gradation
from FS to the LGL syndrome, a saltatory event
seems to take place, transforming FS to the LGL
syndrome. This could be required for clonal LGL
expansion. This does not exclude the possibility, however, that functionally abnormal cells, whether clonal
or not, are present in all FS patients but cannot be
detected by current techniques. Further work, using
more sensitive polymerase chain reaction-based techniques to assess T cell clonality, is required to address
this question.
The mechanisms leading to LGL expansion in
patients with RA may differ from those in patients
without RA. We have previously demonstrated that
the prevalence of HLA-DR4 is increased in LGL
syndrome patients with RA, but not in those without
RA (12). It is of interest that in celiac disease (glutensensitive enteropathy), an immune-mediated disorder
in which there is a close association with HLADQAl”O501;DQB1*0201, there is an increased risk of
enteropathy-associated T cell lymphoma (EATCL)
(13). Not all patients with EATCL have evidence of
celiac disease, but in contrast to the LGL syndrome,
EATCL arises in patients with the same HLA genotype that predisposes to celiac disease (13).
No direct correlation between the levels of
neutrophils and CD3+ ,CD57+ cells in the peripheral
blood was seen in this study. Even if LGLs are
involved in the peripheral suppression or destruction
of neutrophils, it could be argued that a direct relationship between the 2 is too simplistic an expectation for
a potentially complex biologic process. It is of interest
that in RA patients, with active disease, a reduction in
CD8 counts has been reported (14). In this study, a
borderline reduction in CD8 counts was seen in EL4
patients, while the neutrophil and platelet counts were
increased, which is the opposite of FS. FS could result
from a down-regulation of the cytokine(s) putatively
responsible for this (e.g., interleukin-1 [IL-l]/IL-6),
secondary to chronic stimulation. One hypothesis is
that a switch could occur from THl cells involved in
stimulating cellular immunity (and active joint disease
via IL-2 and/or interferon-y) to TH2 cells involved in
humoral immunity (and hence, less active joint disease, and a higher incidence of B cell activity, e.g.,
rheumatoid factor positivity and antineutrophil antibodies via cytokines such as IL-4hL-5).
Similar hypotheses have been proposed in rela-
BOWMAN ET AL
tion to the progression of human immunodeficiency
virus infection to acquired immunodeficiency syndrome (15). In support of this hypothesis, there is
evidence that although the severity of erosive joint
disease in FS is similar to that in RA patients with
similar disease duration (1,16), the disease activity
(i.e., active synovitis) is lower in FS patients (16). The
erosions may reflect the outcome of earlier (i.e.,
“pre-FS”) inflammatory events. We were able to
examine disease activity in a number of FS and RA
patients (Table 5), and were able to confirm this
finding. This reduction in synovitis after the transition
to FS suggests that a change in cytokine pattern may
have occurred. This is indirect support for the TH1/
TH2 hypothesis discussed above. It would bring
W F S into the same immunopathologic framework
as that proposed for lepromatous and tuberculoid
leprosy (17).
One previous study found correlations between
RA duration and age with the percentage expression of
CD3+,CD57+ (18). The suggestion was that chronic
inflammation led to the increased frequency of these
cells. In that study, the raw data were logarithmically
transformed before performing linear regression analysis. There was also a mean age difference of 19 years
between the normal subjects and the RA patients. We
thought that it was more appropriate to use Spearman’s rank correlation coefficient to analyze this question. Table 4 shows that no such correlation was found
in any of the patient groups, despite the fact that the
patients’ mean age and mean CD57/CD3 percentage
expression were similar in the 2 studies. Furthermore,
in order to make a direct comparison with the study of
Dupuy d’Angeac et a1 (18), we also examined our data
using regression analysis following logarithmic transformation. There was again no significant association
for CD57/CD3% expression and either age (P = 0.73)
or the duration of RA (P = 0.44) in the 23 RA patients.
One explanation for this finding would be if disease
activity were closely related to CD57+ expression on
CD3+ cells, leading to a loss of the direct relationship
with age in this sample. Although we were unable to
test this directly from a clinical assessment, none of
the laboratory markers of active disease (elevated
ESR, neutrophil count, and platelet count) showed a
significant correlation with CD3+ ,CD57+ percentage
expression. The LGL patient group has this potential
relationship with RA duration and age uncoupled by
the LGL expansions, while in the FS group, the
lymphopenia may be responsible, although a correlation with age was maintained. Clearly, disease dura-
HEMATOLOGY OF FS AND LGL SYNDROME
tion and patient age are related variables, and it is
important to ensure that an increase with disease
duration is not due to the patient’s increasing age.
In conclusion therefore, despite the close association between FS and the LGL syndrome, evidence
of a gradation from FS to the LGL syndrome was not
seen in this study, thus favoring the hypothesis that a
“transforming event” is required. Both those with FS
alone and those with FS with the LGL syndrome had
low CD4 counts, and while this may contribute to the
increase in infections seen in FS, it may imply further
similarities in the pathogenic mechanisms between
these 2 variants of FS. The findings of this study do not
exclude the hypothesis that all FS patients, including
those without evidence of LGL expansions, share a
common process, but they do suggest a discrete event
that discriminates these 2 subgroups. Recent studies in
a mouse model of autoimmunity, the MRL-lpr mouse
(19), have determined that an abnormality in a single
gene coding for the Fas protein leads to an autoimmune syndrome with similarities to systemic lupus
erythematosus and RA. The Fas protein is required for
apoptosis (programmed cell death), and its absence
leads to uncontrolled expansions of CD3+ ,CD4-,
CD8- T cells (19) in conjunction with autoimmune
phenomena. Clearly, this is not a perfect paradigm for
either RA or FS, but there are notable similarities, and
it has generated enormous interest as a new avenue
for understanding autoimmune disease. FS, with its
immunogenetic homogeneity, association with B cell
hyperactivity, and its CD8+ T cell expansions offers
an obvious starting point for such research.
ACKNOWLEDGMENTS
We would like to thank all our clinical and laboratory
colleagues who contributed to this study. We thank Dr. S.
Schey, Consultant Haematologist, Guy’s Hospital, for performing the blood counts.
REFERENCES
Campion G, Maddison PJ, Goulding N, James I, Ahern MJ,
Watt I, Sansom D: The Felty syndrome: a case-matched study
of clinical manifestations and outcome, serologic features, and
immunogenetic associations. Medicine (Baltimore) 69:69-80,
1990
Meliconi R, Kingsley GH, Pitzalis C, Sakkas L, Panayi GS:
Analysis of lymphocyte phenotype and T cell receptor genotype
in Felty’s syndrome. J Rheumatol 19:1058-1064, 1992
Gonzales-Chambers R, Przepiorka D, Winkelstein A, Agarwal
1259
A, Starz TW, Kline WE, Hawk H: Lymphocyte subsets associated with T cell receptor Pchain rearrangement in patients
with rheumatoid arthritis and neutropenia. Arthritis Rheum
35516-520, 1992
4. Bowman SJ, Bhavnani M, Geddes GC, Conigall V, Boylston
AW, Panayi GS, Lanchbury JS: Large granular lymphocyte
expansions in patients with Felty’s syndrome: analysis using
anti-T-cell receptor VP specific monoclonal antibodies. Clin Exp
Immunol 101:18-24, 1995
5 . Loughran TP Jr: Clonal diseases of large granular lymphocytes.
Blood 82: 1-14, 1993
6. Ligthart GJ, van Vlokhoven PC, Schuit HRE, Hijmans W: The
expanded null cell compartment in ageing: increase in the
number of natural killer cells and changes in T-cell and NK-cell
subsets in human blood. Immunology 59:353-357, 1986
7. Amett FC, Edworthy SM, Bloch DA, McShane DJ, Fries JF,
Cooper NS, Healey LA, Kaplan SR, Liang MH, Luthra HS,
Medsger TA Jr, Mitchell DM, Neustadt DH, Pinals RS, Schaller
JG, Sharp JT, Wilder RL, Hunder GG: The American Rheumatism Association 1987 revised criteria for the classification of
rheumatoid arthritis. Arthritis Rheum 31:315-324, 1988
8. Scott DL, Panayi GS, van Riel PLCM, Smolen J, van de Putte
LBA: Disease activity in rheumatoid arthritis: preliminary report of the Consensus Study Group of the European Workshop
for Rheumatology Research. Clin Exp Rheumatol 10521-525,
1992
9. Prevoo MLL, van ’t Hof MA, Kuper HH, van Leeuwen MA,
van de Putte LBA, van Riel PLCM: Modified disease activity
scores that include twenty-eight-joint counts: development and
validation in a prospective longitudinal study of patients with
rheumatoid arthritis. Arthritis Rheum 38:4448, 1995
10. Spivak JL: Felty’s syndrome: an analytical study. Johns Hopkins Med J 141:156-162, 1977
11. Breedveld FC, Fibbe WE, Cats A: Neutropenia and infections
in Felty’s syndrome. Br J Rheumatol 27:191-197, 1988
12. Bowman SJ, Sivakumaran M, Snowden N, Bhavnani M, Hall
MA, Panayi GS, Lanchbury JS: The large granular lymphocyte
syndrome with rheumatoid arthritis: immunogenetic evidence
for a broader definition of Felty’s syndrome. Arthritis Rheum
37:1326-1330, 1994
13. Howell WM, Leung ST, Jones DB, Nakshabendi I, Hall MA,
Lanchbury JS, Ciclitira PJ, Wright DH: HLA-DRB, DQA and
DQB polymorphism in celiac disease and enteropathyassociated T-cell lymphoma: common features and additional
risk factors for malignancy. Hum Immunol (in press)
14. Duke 0, Panayi GS, Janossy G, Poulter LW, Tidman N:
Analysis of T cell subsets in the peripheral blood and synovial
fluid of patients with rheumatoid arthritis by means of monoclonal antibodies. Ann Rheum Dis 42:357-361, 1983
15. Clerici M, Shearer GM: A THl-TH2 switch is a critical step in
the etiology of HIV infection. Immunol Today 14:107-110, 1993
16. McMahon MJ, Hollis S, Sanders PA, Grennan DM: Articular
disease severity in rheumatoid subjects with and without Felty’s
syndrome. Br J Rheumatol 30:217-219, 1991
17. Kamradt T: T cell unresponsiveness in lepromatous leprosy. J
Rheumatol 20:904-906, 1993
18. Dupuy d’Angeac A, Monier S, Jorgensen C, Gao Q, TravaglioEncinoza A, Bologna C, Combe B, Sany J, RBme T: Increased
percentage of CD3+, CD57+ lymphocytes in patients with
rheumatoid arthritis: correlation with duration of disease. Arthritis Rheum 36:608-612, 1993
19. Steinberg AD: MRL-IprApr disease: theories meet Fas. Semin
Immunol6:55-69, 1994