A Comprehensive Study of Bone Manifestations in Adult Gaucher Disease Type 1 Patients in Argentina

GBA1 as a risk gene for osteoporosis in the specific populations and its role in the development of Gaucher disease

BACKGROUND

Osteoporosis and its primary complication, fragility fractures, contribute to substantial global morbidity and mortality. Gaucher disease (GD) is caused by glucocerebrosidase (GBA1) deficiency, leading to skeletal complications. This study aimed to investigate the impact of the GBA1 gene on osteoporosis progression in GD patients and the specific populations.

METHODS

We selected 8115 patients with osteoporosis (T-score ≤ - 2.5) and 55,942 healthy individuals (T-score > - 1) from a clinical database (N = 95,223). Monocytes from GD patients were evaluated in relation to endoplasmic reticulum (ER) stress, inflammasome activation, and osteoclastogenesis. An in vitro model of GD patient's cells treated with adeno-associated virus 9 (AAV9)-GBA1 to assess GBA1 enzyme activity, chitotriosidase activity, ER stress, and osteoclast differentiation. Longitudinal dual-energy X-ray absorptiometry (DXA) data tracking bone density in patients with Gaucher disease (GD) undergoing enzyme replacement therapy (ERT) over an extended period.

RESULTS

The GBA1 gene variant rs11264345 was significantly associated [P < 0.002, Odds Ratio (OR) = 1.06] with an increased risk of bone disease. Upregulation of Calnexin, NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) and Apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC) was positively associated with osteoclastogenesis in patients with GD. In vitro AAV9-GBA1 treatment of GD patient cells led to enhanced GBA1 enzyme activity, reduced chitotriosidase activity, diminished ER stress, and decreased osteoclast differentiation. Long-term bone density data suggests that initiating ERT earlier in GD leads to greater improvements in bone density.

CONCLUSIONS

Elevated ER stress and inflammasome activation are indicative of osteoporosis development, suggesting the need for clinical monitoring of patients with GD. Furthermore, disease-associated variant in the GBA1 gene may constitute a risk factor predisposing specific populations to osteoporosis.

Anesthetic Approaches and Perioperative Complications of Total Hip Arthroplasty in Gaucher Disease: A Control-Matched Retrospective-Cohort Study

OBJECTIVES

Gaucher disease's (GD) pathophysiology generates anesthetic concerns in total hip joint arthroplasty (THA), and due to its rareness, data on perioperative risks are scarce. This 22-year study at a large reference center addresses anesthetic management and perioperative outcomes in GD.

METHODS

This retrospective-cohort study assessed anesthetic success and safety in 30 THA patients, comparing them with a control-matched group. Data on clinical characteristics, perioperative events, and outcomes were collected. The primary outcome was the success rate of anesthesia induction performance at first attempt. Secondary outcomes were difficult intraoperative course and hemodynamic management, and the development of postoperative complications. The age, sex, weight, body mass index, and primary-to-revision hip arthroplasty ratio were similar in both groups.

RESULTS

There was no significant difference at all-type anesthesia first initiation attempt success. No particular preference by staff anesthetists for general anesthesia or neuraxial procedures was observed. The GD group showed a significantly higher mean of intraoperative packed Red Blood Cell units administered ((0.73 vs. 0.18); (p = 0.038)), higher intraoperative and postoperative platelet transfusion incidence ((5/30 [16.7%] vs. 0/56 [0.00%]; p = 0.004) and (3/30 [10%] vs. 0/56 [0%]; p = 0.040)), and longer mean recovery room length of stay (426 ± 412 vs. 175 ± 140; p = 0.004). Postoperative complications were not significantly different.

Clinical Characteristics, Molecular Background, and Survival of Egyptian Patients With Gaucher Disease Over a 20-Year Follow-up

This study analyzes the general disease characteristics, impact of enzyme replacement therapy (ERT), and overall survival (OS) of 156 Egyptian patients with Gaucher disease (GD) enrolled on hormone replacement from 1998 to 2017. The mean age at diagnosis was 32.46±12.68 months. Anemia was noted at diagnosis in 50%, thrombocytopenia in 30.7%, severe splenomegaly in 58.7%, severe hepatomegaly in 11.9%, and skeletal findings were detected in 24.3% of the patients. The most prevalent GD type was type 3 (54.5%). Twenty-two of type 3 patients had no neurological manifestations at diagnosis, and 12 developed variable central nervous system manifestations during follow-up. The most common neurological features were limited eye movements, oculomotor apraxia, and squint. Of the 60 patients for whom genotypes were obtained, homozygous L444P was the most common (n=35/60, 58.3%). Treatment with ERT (imiglucerase) revealed significant improvements in blood indices, organ volumes, and growth parameters (P<0.05). Ten (11.7%) type 3 patients did not develop any neurological manifestations under ERT over 20 years. Mortality was 16%, and the 20-year OS was 73.3%. We conclude that in Egypt, type 3 is the most prevalent phenotype of GD, and homozygous L444P is the predominant GBA genotype of GD. Early age at diagnosis and treatment with ERT over 20 years revealed significant improvements in disease manifestations, with an OS of 73.3%.

Unraveling the mystery of Gaucher bone density pathophysiology

Gaucher disease (GD) is caused by pathogenic mutations in GBA1, the gene that encodes the lysosomal enzyme β-glucocerebrosidase. Despite the existence of a variety of specific treatments for GD, they cannot completely reverse bone complications. Many studies have evidenced the impairment in bone tissue of GD, and molecular mechanisms of bone density alterations in GD are being studied during the last years and different reports emphasized its efforts trying to unravel why and how bone tissue is affected. The cause of skeletal density affection in GD is a matter of debates between research groups. and there are two opposing hypotheses trying to explain reduced bone mineral density in GD: increased bone resorption versus impaired bone formation. In this review, we discuss the diverse mechanisms of bone alterations implicated in GD revealed until the present, along with a presentation of normal bone physiology and its regulation. With this information in mind, we discuss effectiveness of specific therapies, introduce possible adjunctive therapies and present a novel model for GD-associated bone density pathogenesis. Under the exposed evidence, we may conclude that both sides of the balance of remodeling process are altered. In GD the observed osteopenia/osteoporosis may be the result of contribution of both reduced bone formation and increased bone resorption.