Signs and symptoms
HPP is often associated with a high clinical burden regardless of age at first manifestation.4 While HPP is frequently diagnosed during childhood, it may not be diagnosed until adulthood in some patients, even though patients may have had symptoms for years.1,2

The signs and symptoms may change and accumulate over a patient’s lifetime with the disease manifesting differently in adults and children.4

In adults, common clinical features include muscle weakness, pain, dental abnormalities, abnormal gait, recurrent fractures and pseudofractures.1–3
Real-world data from the Global HPP Registry:1

HISTORY OF HPP-RELATED CLINICAL SIGNS AND SYMPTOMS, CHILDREN (N=121), n/N (%)

Figure adapted from Hogler W, et al. 2019.1

The Global HPP Registry, sponsored by Alexion Pharmaceuticals, is an observational, longitudinal, multinational study with medical history data collected based on patient or parent/guardian recall.1 The registry represents, to date, the largest real-world dataset of patients with HPP (N=269; 121 children, 148 adults).1 The symptoms listed are not exhaustive, and there are other manifestations that may be present in children with HPP.*1 There are multiple signs and symptoms that contribute to each category heading. A full list can be found in Högler W, et al. 2019.1

†Combine generalised body pain, chronic bone pain and chronic muscle pain.‡1 Excludes patients aged <6 months at enrolment.1

‡Excludes patients aged <6 months at enrolment.1
Real-world data from the Global HPP Registry:1

HISTORY OF HPP-RELATED CLINICAL SIGNS AND SYMPTOMS, ADULTS (N=304), n/N (%)

Figure adapted from Seefried L, et al. 20203

The Global HPP Registry, sponsored by Alexion Pharmaceuticals, is an observational, longitudinal, multinational study with medical history data collected based on patient or parent/guardian recall. The registry represents, to date, the largest real-world dataset of patients with HPP (N=269; 121 children, 148 adults).1 This particular analysis was performed on data from 304 adults with a confirmed diagnosis of HPP.3
In infants with HPP, deficient bone mineralisation can be recognised using radiographs9,10
Skeletal signs in children with HPP are common1
Radiographic findings can reveal stress fractures, pseudofractures, facture healing complications and chondrocalcinosis in adult patients with HPP14
HPP is often misdiagnosed and confused with other bone or rheumatic diseases2
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