Acro-osteolysis

Bone mineral density and microarchitecture improvement in a young patient with Hajdu-Cheney syndrome and autosomal dominant polycystic kidney disease treated with alendronate

Introduction

Osteoporosis, typically seen in postmenopausal women, can also affect younger individuals, a condition known as Early-Onset Osteoporosis (EOOP). EOOP may be secondary to various conditions or arise from rare genetic disorders such as Hajdu-Cheney Syndrome (HCS), characterized by systemic bone involvement and fragility fractures.

Case Report

A 14-year-old male presented with a distal left femur fragility fracture. His medical history included spina bifida and bilateral tarsal coalition, with no family history of osteoporosis, and polycystic kidneys associated with a positive family history of autosomal dominant polycystic kidney disease (ADPKD). Laboratory tests were unremarkable, but dual X-ray absorptiometry (DXA) revealed low bone mineral density (BMD), and high resolution peripheral quantitative computed tomography (HR-pQCT) showed decreased volumetric bone density (vBMD), particularly in the cortical bone. At age 17, his kidneys were cystic and mildly enlarged. Whole exome sequencing revealed a pathogenic variant in NOTCH2, confirming the diagnosis of HCS, and a very likely causative variant in PKD1, supporting the diagnosis of ADPKD.The treatment regimen included weekly alendronate, impact exercise, a calcium-rich diet, and vitamin D supplementation. After 3 years, follow-up DXA and HR-pQCT demonstrated significant improvements in BMD and vBMD, mainly in the cortical bone.

Discussion

This case highlights the effectiveness of alendronate in managing osteoporosis in a patient with HCS and ADPKD, despite the current lack of strong supportive evidence. Long-term monitoring revealed substantial improvements in bone density and microarchitecture, underscoring the importance of early diagnosis and intervention for genetic causes of osteoporosis to prevent fracture-related morbidity.

Unraveling the Pathogenesis of Calcinosis in Systemic Sclerosis: A Molecular and Clinical Insight

Dystrophic calcinosis, which is the accumulation of insoluble calcified crystalline materials within tissues with normal circulating calcium and phosphorus levels, is a frequent finding in systemic sclerosis (SSc) and represents a major burden for patients. In SSc, calcinosis poses significant challenges in management due to the associated risk of severe complications such as infection, ulceration, pain, reduction in functional capacity and quality of life, and lack of standardized treatment choices. The exact pathogenesis of calcinosis is still unknown. There are multifaceted factors contributing to calcinosis development, including osteogenic differentiation of cells, imbalance between promoter and inhibitors of mineralization, local disturbance in calcium and phosphate levels, and extracellular matrix as a template for mineralization. Several pathophysiological changes observed in SSc such as ischemia, exacerbated production of excessive reactive oxygen species, inflammation, production of inflammatory cytokines, acroosteolysis, and increased extracellular matrix production may promote the development of calcinosis in SSc. Furthermore, mitochondrial dynamics, particularly fission function through the activity of dynamin-related protein-1, may have an effect on the dystrophic calcinosis process. In-depth investigations of cellular mechanisms and microenvironmental influences can offer valuable insights into the complex pathogenesis of calcinosis in SSc, providing potential targeting pathways for calcinosis treatment.

Identification of a Biallelic Missense Variant in Gasdermin D (c.823G > C, p.Asp275His) in a Patient of Atypical Gorham-Stout Disease in a Consanguineous Family

Gorham-Stout disease (GSD), also called vanishing bone disease, is a rare osteolytic disease, frequently associated with lymphangiomatous tissue proliferation. The causative genetic background has not been noted except for a case with a somatic mutation in KRAS. However, in the present study, we encountered a case of GSD from a consanguineous family member. Whole-exome sequencing (WES) analysis focusing on rare recessive variants with zero homozygotes in population databases identified a homozygous missense variant (c.823G > C, p.Asp275His) in gasdermin D (GSDMD) in the patient and heterozygous in his unaffected brother. Because this variant affects the Asp275 residue that is involved in proteolytic cleavage by caspase-11 (as well as -4 and -5) to generate an activating p30 fragment required for pyroptotic cell death and proinflammation, we confirmed the absence of this cleavage product in peripheral monocytic fractions from the patient. A recent study indicated that a shorter p20 fragment, generated by further cleavage at Asp88, has a cell-autonomous function to suppress the maturation of osteoclasts to resorb bone matrix. Thus, the present study suggests for the first time the existence of hereditary GSD cases or novel GSD-like diseases caused by GSDMD deficiency. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Acro-osteolysis: imaging, differential diagnosis, and disposition review

Acro-osteolysis is the osseous destruction of the hand or foot distal phalanges. The categories of the disease include terminal tuft, midshaft, or mixed types. Recognition of acro-osteolysis is straightforward on radiographs, but providing an accurate differential diagnosis and appropriately recommending advanced imaging or invasive tissue diagnosis can be more elusive. A radiologist's ability to provide advanced assessment can greatly aid clinicians in expedient diagnosis and management of the array of diseases presenting with acro-osteolysis.

Is an association of acro-osteolysis, bone fragility, and enchondromatosis a newfound disease caused by an amplification of PTHLH? A case report

BACKGROUND

Acro-osteolysis (AO) refers to resorption of the distal finger and toe phalanges. It displays two patterns: (i) diffuse AO and (ii) transverse or bandlike AO. AO can be a sign of local distress (e.g. of toxic origin), but is very often a sign of a constitutional or systemic acquired disorder.

CASE PRESENTATION

A 15-year-old girl was referred to a paediatric rheumatologist for recurrent pain in her fingertips. She presented a particular cross-sectional AO associated with the presence of intraosseous cysts and bone fragility with atypical fractures. Initial laboratory tests and radiological examination did not allow an etiological diagnosis. Genetic studies revealed a 12p11.22-p11.23 microduplication of 900 kb including the PTHLH (parathyroid hormone-like hormone) gene, which encodes for a hormone involved in the regulation of endochondral ossification and differentiation of chondrocytes, via its PTHLH receptor.

CONCLUSIONS

To date, 12p11.22-p11.23 duplications have been reported in five families with skeletal abnormalities, and in particular AO and enchondromatosis associated with bone fragility. This new observation, added to the other reported cases, suggests a close relationship between the presence of this microduplication and the skeletal abnormalities found in the patient. We suggest the descriptive name ABES (acro-osteolysis, bone fragility and enchondromatosis syndrome) to designate this disorder.

Silent acro-osteolysis in a patient with psoriatic disease and recurrent micro-trauma

A 42-year-old woman with a 15-year history of psoriatic disease with skin, nail and joint involvement presented for routine follow-up visit. The patient did not complain of relevant articular symptoms, physical examination was unremarkable excepted for feet nail onychodystrophy and routine laboratory tests were unaltered.

Lost bones: differential diagnosis of acro-osteolysis seen by the pediatric rheumatologist

INTRODUCTION

Acro-osteolysis is a radiographic finding which refers to bone resorption of the distal phalanges. Acro-osteolysis is associated with various conditions and its presence should prompt the clinician to search for the underlying etiology. The aim of this review is to discuss disorders with which acro-osteolysis is associated and their distinguishing features, with a focus on the pediatric population.

METHODS

A targeted literature review was performed using the term "acro-osteolysis" in combination with other key terms. The primary search results were supplemented using reference citations. Articles published prior to the year 2000 were included if they described additional associations not encountered in the more recent literature.

RESULTS

Genetic disorders (particularly primary hypertrophic osteoarthropathy and skeletal dysplasias) and rheumatic diseases (particularly psoriatic arthritis and systemic sclerosis) are the most frequently encountered conditions associated with acro-osteolysis in children. Hyperparathyroidism, neuropathy, local trauma and thermal injury, and spinal dysraphism should also be included in the differential diagnosis.

CONCLUSION

Although acro-osteolysis is uncommon, its presence should prompt the clinician to consider a differential diagnosis based on clinical and radiographic features.

The first probable evidence of leprosy in a male individual (17th-19th century AD) unearthed in Northern Portugal (Travanca, Santa Maria da Feira)

OBJECTIVE

This study describes the first evidence of a probable paleopathological case of leprosy from northern Portugal.

MATERIALS

An adult male, skeleton 403, exhumed from the Christian cemetery associated with the church dedicated to Saint Mamede (Travanca, Santa Maria da Feira), dated from the 17th-19th century AD.

METHODS

Standard bioarchaeological methods were used for sex and age-at-death determinations, and leprosy-related bone lesions were identified through macroscopic analysis guided by paleopathological diagnostic criteria.

RESULTS

The macroscopic observation revealed probable leprosy-related skeletal lesions, namely tenuous rhinomaxillary changes, bilateral proliferative periosteal reactions on the tibiae and fibulae, as well as concentric atrophy, acro-osteolysis and ankyloses of foot bones.

CONCLUSIONS

Skeleton 403 represents a probable case of leprosy according to the nature and distribution pattern of bony lesions observed.

SIGNIFICANCE

This finding fills an important gap in the history of leprosy in Portugal. Although historical sources show that the majority of leprosaria were located in the northern part of the country, suggesting that leprosy was more prevalent in this area of Portugal in the past, no paleopathological evidence of this disease was reported for this region to date. Furthermore, the inhumation of a leprosy sufferer in a 17th-19th century AD Christian parish cemetery is deeply imbued with social meaning.

SUGGESTION FOR FUTURE RESEARCH

The future detailed study of the remaining skeletons unearthed from the cemetery of the Church of São Mamede will hopefully reveal further osteological evidence of leprosy in addition to the application of ancient DNA analysis to confirm the presence of the pathogen of this disease. Also, further documentary research is needed in order to expand appreciation of the epidemiological and social impact of leprosy in the 17th-19th century AD Portugal.

Osteitis in Systemic Sclerosis: a nationwide case-control retrospective study (SCLEROS Study)

OBJECTIVE

Systemic sclerosis (SSc) is an autoimmune (AI) connective tissue disorder characterized by skin fibrosis, vasculopathy and dysimmunity. Data regarding osteitis in SSc are scarce.

METHOD

We performed a nationwide multicentre retrospective case-control study including patients with SSc according to the 2013 ACR/EULAR classification, with a diagnosis of osteitis. The objectives of the study were to describe, to characterize, and to identify associated factors for osteitis in patients with SSc.

RESULTS

Forty-eight patients were included. Twenty-six patients (54.1%) had osteitis beneath digital tip ulcers. Physical symptoms included: pain (36/48, 75%), erythema (35/48, 73%), and local warmth (35/48, 73%). Thirty-one (65%) patients had C-reactive protein levels >2 mg/L (8 [2.7 - 44.3] mg/L). On X-ray, CT-scans or MRI, osteitis was characterized by swelling or abscess of soft tissues with acro-osteolysis or lysis in 28 patients (58%). Microbiological sampling was performed in 45 (94%) patients. Most pathogens were Staphylococcus aureus (43.8%); anaerobes and Enterobacteriaceae (29.1%) and Pseudomonas aeruginosa (10.4%). Management comprised antibiotics in 37 (77.1%) patients and/or surgery in 26 (54.2%). Fluoroquinolones were used in 22 (45.8%) patients and amoxicillin + beta-lactamase inhibitor in 7 (14.6%). Six (12.6%) patients relapsed, 6 (12.6%) patients had osteitis recurrence, 15 (32%) sequelae, and 2 patients had septic shock and died.

CONCLUSION

This study confirmed digital tip ulcers as an associated factor for osteitis, and revealed a high rate of functional sequelae. Antimicrobial therapy with oral fluoroquinolone or intravenous amoxicillin and beta-lactamase inhibitor are used as first-line antibiotherapy in SSc patients with osteitis.

Imaging of the spectrum of bony injuries in the diabetic foot: a case series with emphasis on non-Charcot fractures

Diabetes mellitus is associated with an increased risk of lower limb injuries. Peripheral neuropathy, often associated with diabetes, has been demonstrated to increase the risk of fracture almost two-fold and is associated with complications related to fracture healing. Detection of neuropathy-related foot injury is frequently delayed owing to the paucity of symptoms and low degree of suspicion by the clinician. Early recognition of fracture or bone injury and appropriate treatment are critical in preventing debilitating foot deformity and disability. Therefore, the astute radiologist cognizant of these potential injuries plays an essential role in early diagnosis of bony injuries in the diabetic foot. We present a series of radiological images that depict a range of osseous injuries in the diabetic foot and emphasize the role of the radiologist in early recognition of these abnormalities.