Clubbing: an update on diagnosis, differential diagnosis, pathophysiology, and clinical relevance

Examination of the nails: Main signs

Understanding the anatomy of the nail apparatus is a prerequisite for diagnosing and managing various nail disorders. The latter may be associated with systemic pathologies, or accompany infectious, inflammatory, tumoral, toxic or traumatic dermatoses. Before attempting to identify the cause, a rigorous clinical examination should be conducted to screen for elementary lesions that may affect general nail shape, nail surface, subungual attachments, periungual soft tissue or nail color. All of these guide differential diagnosis.

The first case report of an intraosseous epidermoid cyst in the distal phalanx of the index finger with infection resulting in single clubbing finger: A case report and review of the literature

An intraosseous epidermoid cyst at the distal phalanx of the index finger is extremely rare. These cysts are asymptomatic unless ruptured, severely infected, or transformed into malignant squamous cell carcinoma. We present a case of a single clubbing finger in an adult diagnosed with an intraosseous epidermoid cyst in the distal phalanx of the left index finger with no history of pulmonary or cardiovascular diseases. Preoperative MRI showed an expansile lytic lesion with a sclerotic margin. Histopathological examination indicates that there is keratinous cell debris in the cyst with a wall of stratified squamous epithelium, which was the key to the correct diagnosis of an intraosseous epidermoid cyst. Written informed consent was obtained from the patient for publication of this case report and any accompanying images.

Optimizing Screening for Early Disease Detection in Familial Pulmonary Fibrosis (FLORIS): A Prospective Cohort Study Design

Background: Familial pulmonary fibrosis (FPF) can be defined as pulmonary fibrosis in two or more first-degree family members. The first-degree family members of FPF patients are at high risk of developing FPF and are eligible for screening. Reproducible studies investigating risk factors for disease are much needed. Methods: Description of the screening study protocol for a single-center, prospective cohort study; the study will include 200 asymptomatic, first-degree family members of patients with FPF who will undergo three study visits in two years. The primary objective is determining the diagnostic value of parameters for detection of early FPF; the secondary objectives are determining the optimal timing of the screening interval and gaining insight into the natural history of early FPF. The presence of interstitial lung disease (ILD) changes on high-resolution computed tomography of the chest is indicative of preclinical ILD; the changes are determined at baseline. The comparison between the group with and without ILD changes is made for clinical parameters (pulmonary function, presence of digital clubbing, presence of Velcro-like crackles, blood count, liver- and kidney-function testing, patient-reported cough and dyspnea score) and exploratory parameters. Discussion: This study will be the first large-size, prospective, longitudinal cohort study for yearly screening of asymptomatic family members of FPF patients investigating the diagnostic value of parameters, including lung function, to detect early FPF. More effective screening strategies could advance early disease detection.

Diagnosing lung involvement in inflammatory rheumatic diseases-Where do we currently stand?

Lung involvement is the most common and serious organ manifestation in patients with inflammatory rheumatic disease (IRD). The type of pulmonary involvement can differ, but the most frequent is interstitial lung disease (ILD). The clinical manifestations of IRD-ILD and severity can vary from subclinical abnormality to dyspnea, respiratory failure, and death. Consequently, early detection is of significant importance. Pulmonary function test (PFT) including diffusing capacity of the lungs for carbon monoxide (DLCO), and forced vital capacity (FVC) as well as high-resolution computed tomography (HRCT) are the standard tools for screening and monitoring of ILD in IRD-patients. Especially, the diagnostic accuracy of HRCT is considered to be high. Magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) allow both morphological and functional assessment of the lungs. In addition, biomarkers (e.g., KL-6, CCL2, or MUC5B) are being currently evaluated for the detection and prognostic assessment of ILD. Despite the accuracy of HRCT, invasive diagnostic methods such as bronchoalveolar lavage (BAL) and lung biopsy are still important in clinical practice. However, their therapeutic and prognostic relevance remains unclear. The aim of this review is to give an overview of the individual methods and to present their respective advantages and disadvantages in detecting and monitoring ILD in IRD-patients in the clinical routine.

Recognizing skin conditions in patients with cirrhosis: a narrative review

Background: The skin is a major target organ for extrahepatic manifestations of liver diseases, and dermatologic abnormalities are common in patients with hepatic disorders. Clinical examination of the skin, nails and hair can allow for appropriate recognition, early diagnosis and treatment of liver diseases, and improvement in the quality of life and life expectancy of affected patients.Methods: We searched 3 databases (Pubmed,Medline and Embase) and selected studies about cirrhosis related skin manifestations and their pathophysiology.Results: A total of 73 articles were included in the review. Studies displayed the spectrum of cutaneous manifestations related to hormonal and vascular changes as well as nail and hair changes in patients with cirrhosis and/or portal hypertension.Conclusion: Cutaneous alterations are important clues or potential indications in the diagnosis of liver cirrhosis. Familiarity with skin conditions can be promptly diagnosed and appropriate management initiated.KEY MESSAGESManifestations of the liver and skin disorders are interrelated in various ways. Cutaneous changes may be the first clue that a patient has liver disease.The skin is a major target organ for extrahepatic manifestations of liver diseases. A broad range of cutaneous alterations can be present in patients with cirrhosis, such as vascular, nail, hair, hormonal changes, etc.Recognizing these signs is crucial so that potential underlying diseases including liver disease can be promptly diagnosed and appropriate management timely initiated.

An Almost Herbst's Triad: Finger Clubbing and Iron Deficiency Anemia Associated With Severe Gastroesophageal Reflux

Digital clubbing is most commonly caused by pulmonary or cardiac disease, and only rarely it is a manifestation of a gastroenterological disorder. We report a pediatric patient in whom severe gastroesophageal reflux disease caused anemia and digital clubbing, partial clinical presentation of the Herbst triad.

Epidemiology of Digital Clubbing and Hypertrophic Osteoarthropathy: A Systematic Review and Meta-analysis

ABSTRACT

Digital clubbing and hypertrophic osteoarthropathy (HOA) are long-standing clinical entities, but their prevalence have not been synthesized. We aimed to estimate the prevalence of digital clubbing and HOA in people with existing medical conditions.We comprehensively searched PubMed, Embase, and Web of Science to select studies addressing HOA or digital clubbing and published through March 23, 2021. Summary estimates of the prevalence were derived through random-effects meta-analysis and narrative synthesis. The review protocol has been registered with PROSPERO, CRD42021243934.Of 3973 records, we included 142 studies. In adults, the pooled prevalence of digital clubbing was 33.4% (95% confidence interval [CI], 16.6-52.8), 31.3% (95% CI, 22.4-41.1), 27% (95% CI, 9.4-49.5), and 22.8% (95% CI, 10.8-37.6) in subjects with intestinal diseases, interstitial lung diseases, infective endocarditis, and hepatic diseases, respectively. In children and adolescents, the pooled prevalence of digital clubbing was 29.1% (95% CI, 19.4-39.9), 23% (95% CI, 9.0-41.1), 19.5% (95% CI, 4.1-42.4), and 17.1% (95% CI, 9.5-26.5) in subjects with human immunodeficiency virus infection, hemoglobinopathies, cystic fibrosis, and tuberculosis. The pooled prevalence of HOA was 10.1% (95% CI, 2.0-23.1) in adults with cancers, and 5% (95% CI, 2.5-8.2) in children and adolescents with cystic fibrosis.In conclusion, the prevalence of digital clubbing varied across disease groups in both adults and children. Full-spectrum HOA was mostly reported in adults with liver disease and cancers, and in children and adolescents with cystic fibrosis.

Finger clubbing in inflammatory bowel disease: association with upper small bowel lesions and need of surgery in Crohn's disease

OBJECTIVE

Finger clubbing has been associated with inflammatory bowel disease (IBD).

AIMS

In a prospective single-center study, we aimed to assess the frequency of finger clubbing in a cohort of IBD patients. Whether finger clubbing is associated with clinical characteristics of IBD was also investigated.

METHODS

IBD patients with a detailed clinical history were enrolled. Finger clubbing was assessed by visual inspection. Data were expressed as median (range), chi-square, t-test. Multivariate logistic regression analysis was used to assess risk factors for finger clubbing, when considering demographic and clinical characteristics, smoking habits and chronic pulmonary diseases (CPD).

RESULTS

Finger clubbing was searched in 470 IBD patients: 267 Crohn's disease and 203 ulcerative colitis. Finger clubbing was more frequent in Crohn's disease than in ulcerative colitis: 45/267 (16.8%) vs. 15/203 (7.3%) [odds ratio (OR), 2.54 (1.37-4.70); P = 0.003]. Crohn's disease involved the ileum (59.9%), colon (4.5%), ileum-colon (25.8%) and upper gastrointestinal (GI) (9.8%). Ulcerative colitis extent included proctitis (E1) (13.4%), left-sided (E2) (43.3%) and pancolitis (E3) (43.3%). Upper GI lesions, but not other Crohn's disease localizations, were more frequent in patients with finger clubbing [9/45 (20%) vs. 17/222 (7.7%); P = 0.032]. Crohn's disease-related surgery was more frequent in patients with finger clubbing [36/45 (80%) vs. 107/222 (48.1%); P < 0.001]. In Crohn's disease, the only risk factors for finger clubbing were upper GI lesions and Crohn's disease-related surgery [OR, 2.58 (1.03-6.46), P = 0.04; OR, 4.07 (1.86-8.91), P = 0.006]. Ulcerative colitis extent was not associated with finger clubbing [E1: OR, 0.27 (0.02-3.44), P = 0.33; E2: OR, 0.93 (0.24-3.60), P = 0.92; E3:OR, 0.64 (0.22-1.86), P = 0.59]. In ulcerative colitis, but not in Crohn's disease, finger clubbing was more frequent in smokers [13/15 (86.6%) vs. 99/188 (52.6%); P = 0.01] and in patients with CPD [5/15 (33.3%) vs. 16/188 (8.5%); P = 0.002]. Smoking and CPD were the only risk factors for finger clubbing in ulcerative colitis [OR, 7.18 (1.44-35.78), P = 0.01; OR, 10.93 (2.51-47.45), P = 0.001].

CONCLUSION

In the tested IBD population, finger clubbing was more frequent in Crohn's disease than in ulcerative colitis. In Crohn's disease, upper GI lesions and history of Crohn's disease-related surgery were risk factors for finger clubbing, suggesting the possible role of finger clubbing as a subclinical marker of Crohn's disease severity.

Unilateral clubbing-like digital thickening as a clinical manifestation of low-flow vascular malformations: a series of 13 cases

BACKGROUND

Digital clubbing is a well-known clinical sign characterized by thickening of the distal phalanges of the fingers and toes. Unilateral clubbing occurs less frequently. A previous report showed for the first time two cases of unilateral clubbing as a clinical manifestation of lower limb venous malformation. The objective of the present study is to describe a series of 13 patients with a low-flow vascular malformation where a clubbing-like unilateral digital thickening is also observed.

METHODS

All patients were retrospectively included after reviewing clinical photographs from a vascular malformations database.

RESULTS

A total of 13 patients with low-flow vascular malformations were included in this study. The mean age at diagnosis was 11 years (range 5-26 years) with a female predominance (nine patients). The most frequent vascular malformation collected was a blue rubber bleb nevus syndrome in four patients, followed by common venous malformations in three patients. All patients characteristically exhibited a clubbing-like digital thickening. Seven patients had foot involvement and six patients hand involvement.

CONCLUSIONS

Although the number of cases is limited, our study is the first series of cases where a clubbing-like digital thickening is described in patients with a low-flow vascular malformation. The unilateral presence of clubbing or pseudoclubbing should lead to the suspicion of an underlying vascular malformation.

Nail is Systemic Disorders: Main Signs and Clues

Describing and listing all nail symptoms and signs in systemic disorders has already been widely detailed in dedicated textbooks. To be tutorial, this article described most common nails signs and the systemic disorders one may encounter in routine dermatologic consultation. Capsule summaries are presented for each section.

Painful nails: A practical approach to the diagnosis and management of painful nail conditions

Because several nail disorders share similar clinical features, their diagnosis and management can be challenging to clinicians. The physical examination may disclose localized abnormalities or point to an underlying systemic disease, requiring additional workup. Furthermore, cosmetic distress and nail-related symptoms (e.g., tingling, stinging, numbness, and pain) are common factors that influence the patient's search for medical assistance. Nail pain (i.e., onychalgia) can accompany both localized and systemic pathology. Onychalgia can be acute or chronic according to the time of evolution; patients may describe it as intermittent or constant, and as a throbbing, burning, sharp, or shooting sensation denoting the nature of the pain. It may be exacerbated by colder temperatures, touch, and increased activity (e.g., manipulating objects, walking). We present four main groups of conditions that might cause nail pain: nail tumors, nail deformities, inflammatory or infectious diseases, and external or traumatic agents. Our article includes an overview of the clinical features, as well as diagnosis and management pearls for each entity. Physicians (dermatologists and nondermatologists) should be aware that abnormalities of the ungual and subungual space are not exclusive of dermatological disorders but may also be present in noncutaneous contexts.

Cutaneous Paraneoplastic Syndromes with Nail Involvement

The cutaneous paraneoplastic syndromes are rare and intrinsically devoid of any neoplastic nature. The manifestations on the skin and the nails are due to various mechanisms caused by the tumor, either due to production of bioactive substances or in response to it. These disorders evolve in parallel to the malignancy, in that, they regress when the tumor is removed and reappear in the case of tumor recurrence. The aim of this article is to aid with the early recognition of the signs, leading to the early detection of cancer and therefore to better clinical outcomes for the patients.

Clubbed Digits Presumably Caused by Lubiprostone

Digital clubbing has been regarded as an important sign in medicine. A 33-year-old woman with no history of hepatic, pulmonary, or malignant disease was referred to our hospital. She had been taking lubiprostone every day for three years for constipation. Clubbing in her upper and lower limb digits began gradually about two years ago. The results of laboratory investigations were almost normal. We suspected the clubbed digits were a side effect of lubiprostone and confirmed that the levels of urinary prostaglandin E2 (PGE2), which can cause clubbed digits, were elevated. Thus, we instructed the woman to stop taking lubiprostone and monitored this lab value. However, the value continued to rise over 2 months to 41.9 μg/g Cr. During that time, she had been taking sennoside A B calcium instead of lubiprostone for constipation. Since sennoside A B calcium also has the effect of increasing PGE2, we ordered the discontinuation. Her urinary PGE2 to creatinine level normalized, and the clubbing improved after the discontinuation of these two medications.

Can we identify cystic fibrosis from skeletal remains? A proposed differential diagnosis

Cystic fibrosis (CF) is the most common genetic disease within populations with European ancestry and affects approximately 60,000 individuals living in North America and Europe. With recent medical advancement, the life span of CF patients has been extended by decades and bone disease has been observed as a common complication of long-term survivors. In addition to bone disease and associated bone fracturing, living CF patients have a unique etiology of chronic sinusitis, which manifests as a medial bulge in the lateral walls of the nasal aperture, distinct from non-CF chronic sinusitis. We suggest that available data from medical literature is sufficient evidence to indicate that CF can be identified during skeletal analysis, but future work is needed to quantify the sensitivity of the lesions for confirming a CF diagnosis.

A rare presentation of Takayasu’s arteritis- unilateral finger clubbing – case report

Background

Takayasu’s arteritis (TA) is a granulomatous, large vessel vasculitis with a preponderance for young women. The inflammation results in disruption of the arterial endothelium causing stenosis, endoluminal thrombosis and aneurismal dilatation. Early disease presentation is with nonspecific general symptoms, and in such instances, the diagnosis can be missed. Unilateral clubbing is a manifestation of myriad of diseases, but is not a common sign of TA. In medical literature, only three such cases have been reported.

Case presentation

We present a 24-year-old female who presented with multiple constitutional symptoms such as arthralgia, malaise, poor appetite and two episodes of syncope over 3 months’ duration. On examination, unilateral finger clubbing was observed in the right hand, with very low volume radial, ulnar and brachial artery pulses on the ipsilateral side. Her blood pressure measured on the unaffected arm, was normal. Inflammatory markers were elevated and magnetic resonance angiogram (MRA) confirmed TA.

Conclusion

Although rare, unilateral clubbing may be a manifestation of TA. Therefore, detection of unilateral clubbing should raise a strong clinical suspicion of TA and prompt early diagnosis and initiation of treatment.

Worsening and newly diagnosed paraneoplastic syndromes following anti-PD-1 or anti-PD-L1 immunotherapies, a descriptive study

Background

Paraneoplastic syndromes (PNS) are autoimmune disorders specifically associated with cancer. There are few data on anti-PD-1 or anti-PD-L1 immunotherapy in patients with a PNS. Our objective was to describe the outcome for patients with a pre-existing or newly diagnosed PNS following the initiation of anti-PD-1 or anti-PD-L1 immunotherapy.

Methods

We included all adult patients (aged ≥18) treated with anti-PD-1 or anti-PD-L1 immunotherapy for a solid tumor, diagnosed with a PNS, and registered in French pharmacovigilance databases. Patients were allocated to cohorts 1 and 2 if the PNS had been diagnosed before vs. after the initiation of immunotherapy, respectively.

Findings

Of the 1304 adult patients screened between June 27th, 2014, and January 2nd, 2019, 32 (2.45%) had a PNS and were allocated to either cohort 1 (n = 16) or cohort 2 (n = 16). The median (range) age was 64 (45–88). The tumor types were non-small-cell lung cancer (n = 15, 47%), melanoma (n = 6, 19%), renal carcinoma (n = 3, 9%), and other malignancies (n = 8, 25%). Eleven (34%) patients presented with a neurologic PNS, nine (28%) had a rheumatologic PNS, eight (25%) had a connective tissue PNS, and four (13%) had other types of PNS. The highest severity grade for the PNS was 1–2 in 10 patients (31%) and ≥ 3 in 22 patients (69%). Four patients (13%) died as a result of the progression of a neurologic PNS (encephalitis in three cases, and Lambert-Eaton syndrome in one case). Following the initiation of immunotherapy, the PNS symptoms worsened in eight (50%) of the 16 patients in cohort 1.

Interpretation

Our results show that PNSs tend to be worsened or revealed by anti-PD-1 or anti-PD-L1 immunotherapy. Cases of paraneoplastic encephalitis are of notable concern, in view of their severity. When initiating immunotherapy, physicians should carefully monitor patients with a pre-existing PNS.

Digital clubbing occurring in intrathoracic Hodgkin lymphoma: A case report

RATIONALE

Digital clubbing is rarely associated with lymphoma. This study reports a case of intrathoracic Hodgkin lymphoma with digital clubbing and reviews the current literature regarding the clinical characteristics of this condition.

PATIENT CONCERN

A 21-year-old woman presented with a 3-month history of cough and 1 month of fever, with apparent digital clubbing. A computed tomography (CT) scan of the lungs revealed a large pulmonary mass.

DIAGNOSIS

A CT-guided transthoracic needle biopsy was conducted. Pathology determined a diagnosis of Hodgkin lymphoma.

INTERVENTIONS

The patient underwent 6 courses of chemotherapy and intensification, followed by autografting.

OUTCOMES

The patient recovered and a complete hematological remission was obtained. The patient is alive with no evidence of disease 60 months after diagnosis, with the digital clubbing of the fingers and toes completely resolved.

CONCLUSION

Patients with digital clubbing and intrathoracic lesions need to be examined carefully to determine tumor malignancy.

Nail clubbing in laxative abuse: case report and review of the literature

BACKGROUND

The link between clubbing and laxative abuse has been reported several times in the literature, in all cases in young females. The nature of this relationship is not understood.

CASE

A young female, with no history of hepatic, pulmonary or malignant disease was found to have nail clubbing in the context of laxative abuse. A literature review revealed several similar cases.

CONCLUSION

Laxative abuse is an important consideration in the assessment of clubbing in populations at risk of eating disorders, to prevent over-investigation and facilitate management of the eating disorder itself. This case highlights a new clinical presentation of an eating disorder.

CASE

A 36-year-old woman was being reviewed by a renal specialist for renal impairment and electrolyte disturbances, in the context of a background of multiple renal calculi 4 years prior, hypokalaemia and hypercalcaemia. The attending nephrologist brought attention to her nails, which demonstrated clubbing. She stated that she had had clubbing for 10 years, and that it was of gradual onset and not associated with any pain. There was no history of hepatic, cardoipulmonary or malignant disease.

Digital Clubbing Is Associated with Higher Serum KL-6 Levels and Lower Pulmonary Function in Patients with Interstitial Lung Disease

Background

Although digital clubbing is a common presentation in patients with interstitial lung disease (ILD), little has been reported regarding its role in assessing patients with ILD. This study evaluated patients with ILD for the presence of clubbing and investigated its association with clinical data.

Methods

We evaluated patients with ILD who visited the teaching hospital at which the study was conducted, between October 2014 and January 2015. Clubbing, evaluated using a Vernier caliper for individual patients, was defined as a phalangeal depth ratio > 1. We examined the association of clubbing with clinical data.

Results

Of 102 patients with ILD, we identified 17 (16.7%) with clubbing. The partial pressure of oxygen in arterial blood was lower (65.2 ± 5.9 mmHg versus 80.2 ± 3.1 mmHg; p=0.03), serum Krebs von den Lugen-6 (KL-6) levels were higher (1495.0 ± 277.4 U/mL versus 839.1 ± 70.2 U/mL; p=0.001), and the percent predicted diffusing capacity of carbon monoxide was lower (50.0 ± 6.0 versus 73.5 ± 3.1; p=0.002) in these patients with clubbing.

Conclusions

Patients with clubbing had lower oxygen levels, higher serum KL-6 levels, and lower pulmonary function than those without clubbing.

Ankylosing spondylitis does not increase the risk of neurogenic heterotopic ossification in patients with a spinal cord injury: a retrospective cohort study

STUDY DESIGN

Retrospective chart review.

OBJECTIVES

The present study was performed to analyze the impact of ankylosing spondylitis (AS) in developing heterotopic ossification (HO) in patients following spinal cord injury.

SETTING

Department of Spinal Cord Injury and Department of General and Trauma Surgery, BG-University Hospital Bergmannsheil Bochum, Ruhr-University Bochum, Germany.

MATERIALS AND METHODS

Between January 2003 and December 2015, 67 patients with AS and SCI were included in the study. The control group consisted of 141 patients with SCI and without AS. The definitive diagnosis of HO was made via magnetic resonance imaging or computed tomography. Primary outcome measure was to analyze the impact of AS on the development of HO.

RESULTS

Fifteen out of 67 AS patients (22.4%) had a diagnosed HO. In the control group, 28 of 141 patients (19.9%) suffered from HO. Patients with AS had no significant higher risk for HO development compared with patients without AS (RR=1.16; 95% CI=0.65-2.09). However, patients with a complete neurological deficit had a twofold higher risk for HO development (RR=2.55; 95% CI=1.26-5.16).

CONCLUSIONS

AS does not increase the risk for HO development in patients with spinal cord injury.

Enchondroma in the distal phalanx of the finger: An observational study of 34 cases in a single institution

The goal of our study was to report the clinical presentation, treatment, and complications of enchondroma in the distal phalanx of the finger. This was a retrospective study of 34 patients (19 women and 15 men) who underwent surgery between May 2004 and September 2012 for enchondroma in the distal phalanx of the finger. The average age of the patients was 39.38 ± 10.97 years old (range 14-59). The presenting symptoms and imaging features were recorded. The surgical procedure was performed under regional or general anesthesia. The surgical technique involved removal of tumors by opening a cortical window and curetting the cavity. The defects were filled with an injectable calcium phosphate cement. All patients received follow-up in our outpatient clinic every 6 months. Expansion of bone or thinning of the cortex present in the radiological imaging, including anteroposterior and lateral plain radiographs of the fingers, was used to assess for tumor recurrence. The observational end-point was reoperation.All tumors were confirmed as enchondromas by the pathological results. None of the patients had a tumor recurrence. Three patients (9% of cases) developed an infection. After antibiotic treatment, 2 patients were cured, and 1 patient required an amputation. Enchondroma in the distal phalanx of the finger presents with a variety of clinical symptoms. Injectable calcium phosphate cement is adequate for bone grafting. Postoperative infection is more common than tumor recurrence. If patients have an infection or bilateral bone cortex defects, bone grafting is challenging.

LEVEL OF EVIDENCE

Therapeutic study, Level IV.

Clubbing and hypertrophic osteoarthropathy: insights in diagnosis, pathophysiology, and clinical significance

BACKGROUND

Digital clubbing and hypertrophic osteoarthropathy (HOA) form a diagnostic challenge. Subtle presentations of clubbing are often missed. The underlying pathophysiology remains unclear. Establishing a differential diagnosis based on nonspecific signs can be cumbersome. Finally, the prognostic value of clubbing and HOA remains unclear.

OBJECTIVE

This article reviews clinical criteria and pathophysiology of clubbing and HOA. A diagnostic algorithm is proposed, based on etiology and current insights. The prognostic impact on associated diseases is discussed.

METHODS

The Internet databases Medline and Embase were searched. Articles were selected based on relevance of abstract, article type and impact of the journal.

RESULTS

Diagnostic criteria include Lovibond's profile sign, distal/interphalangeal depth ratio and Schamroth's sign. Three pathophysiological causes of clubbing can be distinguished: hypoxia, chronic inflammation and aberrant vascularization. A prominent role for vascular endothelial growth factor is suggested. Associated symptoms and clinical signs should guide the initial diagnostic evaluation. Finally, clubbing is a negative prognostic factor in certain pulmonary disorders, including cystic fibrosis.

Cutaneous lesions and finger clubbing uncovering hypocomplementemic urticarial vasculitis and hepatitis C with mixed cryoglobulinemia

Urticarial vasculitis is a rare clinicopathologic entity characterized by urticarial lesions that persist for more than 24 hours and histologic features of leukocytoclastic vasculitis. Patients can be divided into normocomplementemic or hypocomplementemic. The authors report the case of a healthy 49-year-old woman with a 1-year history of highly pruritic generalized cutaneous lesions and finger clubbing. Laboratory tests together with histopathologic examination allowed the diagnosis of hypocomplementemic urticarial vasculitis, chronic hepatitis C and type II mixed cryoglobulinemia. The patient started symptomatic treatment and was referred to a gastroenterologist for management of the hepatitis C, with progressive improvement of the skin condition. The development of hypocomplementemic urticarial vasculitis in the context of chronic hepatitis C is exceedingly rare and possible pathogenic mechanisms are discussed.

Paraneoplastic syndromes in rheumatology

For patients that present with musculoskeletal symptoms, diagnostic procedures carried out by physicians and rheumatologists are primarily aimed at confirming or excluding the occurrence of primary rheumatic diseases. Another important trigger for musculoskeletal disease, however, is the presence of a tumour. Careful clinical investigation and knowledge of the gestalt of musculoskeletal syndromes related to respective tumour entities is of utmost importance for the diagnosis of paraneoplastic rheumatic diseases such as hypertrophic osteoarthropathy, paraneoplastic polyarthritis, RS3PE syndrome, palmar fasciitis and polyarthritis, cancer-associated myositis and tumour-induced osteomalacia. This places great responsibility on rheumatologists in diagnosing malignancies and referring the patient for effective treatment. The selective influence of tumours on musculoskeletal tissue is surprising and indicates that tumours alter tissues such as the periosteum, synovial membrane, subcutaneous connective tissue, fascia, muscles and bones by specific molecular processes. Some of the underlying mechanisms have been unravelled, providing valuable information on the physiologic and pathophysiologic roles of mediators such as vascular endothelial growth factor and fibroblast growth factor 23.

Nail abnormalities associated with systemic pathologies

Nail abnormalities can arise in conjunction with or as a result of systematic pathologies. These pathologies include single-organ diseases, multisystemic diseases, and drug-induced insults. Clinical signs associated with these conditions include dyschromias, vascular alterations, periungual tissue changes, textural dystrophies, contour alterations, and growth-rate alterations. The associated systemic pathologies may affect any part of the nail apparatus, including the nail matrix, the nail plate, the nail bed, the underlying vasculature, and the periungual tissues. The anatomical location and extent of damage determine the clinically manifested anomaly.

Validation of the megakaryocyte fragmentation theory of finger clubbing in patients with cardiopulmonary diseases

Dickinson and Martin had proposed that finger clubbing is caused by distal impaction of large-sized platelets that escape physiological fragmentation in lung vasculature. Empirical evidence to support this theory, however, is limited and conflicting. Moreover, this theory has not been verified in patients with lung diseases. We conducted a cross-sectional analytic study to validate the megakaryocyte fragmentation theory in patients with cardiopulmonary diseases. We studied four groups - patients with cyanotic heart diseases and clubbing (n = 20); patients with non-malignant lung diseases and clubbing (n = 25); patients with non-malignant lung diseases but no clubbing (n = 25); and healthy individuals (n = 25). We measured the distal phalangeal depth ratio, estimated the platelet volume indices, and examined the peripheral blood smear for the presence of large platelets. We found that patients with clubbing due to cyanotic heart diseases had a significantly lower platelet count (median [IQR] 201 [157-241] vs. 303 [258-334] × 10(3)/μl; p < 0.001), higher platelet volume (mean difference, Δ [95% CI] = 0.93 fl [0.37-1.49 fl]; p = 0.002) and platelet large cell ratio (Δ = 7.99% [3.71%-12.26%]; p < 0.001) as compared to healthy individuals. They were also significantly more likely to have large platelets on peripheral blood smear as compared to healthy individuals (9/25 vs. 0/25; p = 0.002). However, in patients with lung diseases, irrespective of the presence or absence of clubbing, platelet count and platelet volume indices were not different from healthy individuals. Our findings support the megakaryocyte fragmentation theory of finger clubbing in patients with cyanotic heart diseases. However, this theory does not explain the clubbing seen in non-malignant lung diseases.

Single clubbed finger caused by an enchondroma of the distal phalanx: an unusual clinical presentation

Single clubbed finger is an extremely rare condition that may show the presence of an underlying neoplasm of the distal phalanx. We describe a case of clubbing in a young adult patient with an enchondroma of the ring finger distal phalanx. The patient had a history of antecedent trauma to the left ring finger, suggesting the diagnosis of intraosseous epidermoid cyst rather than enchondroma. The lesion was successfully treated by curettage and packing of the bony defect with a synthetic bone substitute. Histologically, the tumour consisted of small, uniform chondrocytes without cytologic atypia. At the seven months follow-up, the patient had no evidence of recurrence, with a nearly normal-looking finger. We suggest that enchondroma should be considered in the differential diagnosis of clubbing in a single digit.

Clinical diagnostic clues in Crohn's disease: a 41-year experience

Determining the diagnosis of Crohn's disease has been highly difficult mainly during the first years of this study carried out at the Pontificia Universidad Catolica (PUC) Clinical Hospital. For instance, it has been frequently confused with Irritable bowel syndrome and sometimes misdiagnosed as ulcerative colitis, infectious colitis or enterocolitis, intestinal lymphoma, or coeliac disease. Consequently, it seems advisable to characterize what the most relevant clinical features are, in order to establish a clear concept of Crohn's disease. This difficulty may still be a problem at other medical centers in developing countries. Thus, sharing this information may contribute to a better understanding of this disease. Based on the clinical experience gained between 1963 and 2004 and reported herein, the main clinical characteristics of the disease are long-lasting day and night abdominal pain, which becomes more intense after eating and diarrhoea, sometimes associated to a mass in the abdomen, anal lesions, and other additional digestive and nondigestive clinical features. Nevertheless, the main aim of this work has been the following: is it possible to make, in an early stage, the diagnosis of Crohn's disease with a high degree of certainty exclusively with clinical data?

Risk factors for heterotopic ossification in patients with spinal cord injury: a case-control study of 264 patients

STUDY DESIGN

Case-control study.

OBJECTIVE

We designed a case-control study to analyze the risk factors associated with the development of heterotopic ossification (HO) in patients with traumatic spinal cord injury.

SUMMARY OF BACKGROUND DATA

Patients with spinal cord injury have a high risk of developing HO, although the exact etiopathogenesis is still unknown. Several factors are known to be potential risk factors. However, we are not aware of any large clinical studies evaluating the risk factors for HO.

METHODS

Patients who were treated for a traumatic spinal cord injury in our hospital, and who subsequently developed HO, were identified by querying the electronic database at our hospital from 2002 to 2010. One hundred thirty-two patients and 132 controls were included. Our primary outcome measures were the risk of developing HO according to whether the patient had experienced a complete spinal cord lesion according to American Spinal Injury Association Impairment Scale; tetraplegia or paraplegia; cervical, thoracic, or lumbar injury; severe chest trauma; and the time interval between injury and surgery. Secondary risk factors explored were patient age; sex; presence and number of comorbidities; length of hospital and intensive care unit stay; associated traumatic injuries; presence of spasticity, pressure ulcers, deep venous thrombosis, and urinary tract infection; and pulmonary complications, such as pneumonia and necessity of tracheostomy.

RESULTS

Patients with associated spasticity and thoracic trauma, complete lesion, pneumonia, presence of tracheostomy, and urinary tract infection had a higher risk of developing HO.

CONCLUSION

Adequate management of potential risk factors could help reduce the overall incidence of HO and outcome in patients with traumatic spinal cord injury.

Nail disorders as signs of pediatric systemic disease

Herein, we describe some of the more common changes in the nail unit that can be seen in systemic diseases in children. Changes that can be seen are not limited to those discussed in the following pages. The presence of changes on multiple nails is suggestive of a systemic cause in an ill child. However, multiple nails can also be affected in primary inflammatory disorders and infections of the nail unit. When evaluating a pediatric patient with a nail disorder, it is important to perform a complete physical examination of the skin and oral mucosa, as other clues to the diagnosis of the nail problem may be found. A comprehensive family history is also important to uncover possible syndromic associations with nail disease or diseases that can manifest with nail changes.

[Hypertrophic osteoarthropathy. Bamberger-Marie disease]

Hypertrophic osteoarthropathy (HOA) is the classical neoplastic disease in rheumatology characterized by a combination of digital clubbing, joint and bone pain, and proliferative periostitis. This combination of symptoms should initiate an intensive search for an underlying malignant disease usually of thoracic organs. Here we report the case of a patient with HOA and neuroendocrine carcinoma of the esophagus. Other non-malignant disorders of the lungs, heart and other organs should be considered in the differential diagnosis. In addition, rare cases of a primary hereditary form of HOA exist and the genetic background has recently been discovered. Thus, new insights into the pathophysiology have improved diagnostic and therapeutic options for this disorder.