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CLINICAL REPORT
Aquagenic Pruritus in Polycythemia Vera: Clinical Characteristics
Edyta LELONEK 1 , Łukasz MATUSIAK 1 , Tomasz WRÓBEL 2 and Jacek C. SZEPIETOWSKI 1
1
Department and Clinic of Dermatology, Venereology and Allergology, and 2 Department and Clinic of Hematology, Blood Neoplasms and
Bone Marrow Transplantation, Wroclaw Medical University, Wrocław, Poland
Aquagenic pruritus is one of the main clinical featu-
res of polycythemia vera. The aim of this study was to
analyse the clinical characteristics of aquagenic pru-
ritus. The study group comprised 102 patients with
molecularly confirmed polycythemia vera. Demograp-
hic data, data on disease history, polycythemia vera
status and treatment modalities were collected. Mo-
reover, various clinical features of aquagenic pruritus
(including intensity, localization, quality, descriptors)
and the most common factors responsible for its ag-
gravation or alleviation were examined. Aquagenic
pruritus was observed in 41.2% of individuals, mean
duration 6.6 ± 8.6 years, and its onset was noticed in
the majority of patients (52.4%) before the diagnosis
of polycythemia vera. The mean intensity of aquagenic
pruritus was 4.8 ± 1.9 points (visual analogue scale).
One-third of patients with aquagenic pruritus avoided
any contact with water. Antipruritic treatment was re-
ceived only by 3 patients. Aquagenic pruritus seems to
be an important, but frequently neglected, symptom in
patients with polycythemia vera.
Key words: aquagenic pruritus; polycythemia vera; itch.
Accepted Feb 13, 2018; Epub ahead of print Feb 13, 2018
Acta Derm Venereol 2018; 98: 496–500.
Corr: Jacek C. Szepietowski, Department and Clinic of Dermatology, Ve-
nereology and Allergology, Wroclaw Medical University, Chałubińskiego
1, PL-50-368 Wrocław, Poland. E-mail: [email protected]
T
he causes, effects and treatment of polycythemia
vera (PV)-associated pruritus and, more specifically,
aquagenic pruritus (AP) are relatively unknown. The aim
of this study was to broaden our understanding of this
detrimental and life-inhibiting condition.
PV is one of the main clonal, BCR-ABL-negative,
haematological malignant neoplasms caused by muta-
tions of a cytoplasmic tyrosine kinase – Janus kinase
2 enzyme (either JAK2V617F or JAK2 exon 12) (1, 2).
The homozygotic mutations of JAK2 were found to be
significantly more often associated with AP (3).
AP was first reported as an important clinical feature
of PV in 1985 (4), although the disease was described
earlier, in 1970, by Shelley (5), who distinguished it
from aquagenic urticaria. AP is characterized by the
development of intense itching, stinging, tingling or
burning sensations without visible skin lesions and is
brought on by contact with water of any temperature
(4). The estimated prevalence of PV-associated pruritus
varies and, according to published data, is reported in
doi: 10.2340/00015555-2906
Acta Derm Venereol 2018; 98: 496–500
31–69% of patients (6–8). It has significant influence
on patients’ quality of life and personal hygiene, as it
can lead to patients abandoning bathing completely (9).
Although AP is recognized as the most excruciating
aspect of PV, knowledge of its pathophysiology, fre-
quency and precise character is limited. Moreover, the
lack of insight into the mechanism of cutaneous induction
of PV-associated AP makes treatment of this condition
constantly challenging. Therefore, the aim of this study
was to analyse the clinical features of AP.
METHODS
Patients
The material for the study was collected between April 2015 and
June 2016. The study group comprised 102 patients (65 women and
37 men) with confirmed PV according to the WHO criteria. All of
the patients presented with JAK2V617F mutation. The age range
of studied individuals was 30–90 years (mean 66.9 ± 12.7 years).
Individuals with AP constituted a group for further analysis,
with a detailed examination of pruritus. Patients presenting other
types of itching (4/102; 3.9%) were excluded. None of the patients
reported the presence of pruritus previously or its spontaneous
resolution. Detailed characteristics of the study group are given
in Table I.
The study was approved by the ethics committee of Wroclaw
Medical University (number 355/2016).
Study design
Demographic data, disease history, PV status and treatment
modalities were collected from all participants. AP intensity was
evaluated with a visual analogue scale (VAS), verbal rating scale
(VRS) and a 4-item Itch Questionnaire (10–13).
Patients were asked to indicate on a 10-point VAS scale, the
maximum and mean intensity of their pruritus during the last 3
days. Scores ranged from 0 (no itch) to 10 points (worst imagina-
ble itch). VAS cut-off points are as follows: mild pruritus (0–< 3
points), moderate pruritus (≥ 3–7 points), severe pruritus (≥ 7–9
points), and very severe pruritus (≥ 9 points) (10).
Participants assessed their itch intensity on the VRS by selec-
ting one of the following options: “none”, “mild”, “moderate”,
“severe”, or “very severe”.
The 4-item Itch Questionnaire was used to estimate the extent
(1–3 points), intensity (1–5 points), frequency (1–5 points) and
sleep disturbances (0–6 points) caused by AP during the 3 days
prior to the examination. Ratings ranged from 3 (mild pruritus)
to 19 points (very severe pruritus). This instrument was used pre-