Computerized tomography of proximal femoral trabecular patterns

A comprehensive imaging and pathologic investigation utilizing patients and cadaver material was performed in order to identify the normal trabecular pattern of the proximal femur and to assess alterations in this pattern in various disorders. Patients and specimens were studied with computed tomography (CT), including three-dimensional CT image reconstruction in selected cases and plain film radiography. The CT imaging of the proximal femur provides insight into the dynamic state of bone in this region. Despite limited resolution, three-dimensional CT image reconstruction is capable of portraying the concentration and orientation of major trabeculae in the proximal femur. Increased trabecular spacing occurs in osteoporosis and is well depicted by CT. Proliferation and thickening of the most superior subchondral primary compressive trabeculae is an early sign of osteoarthritis. In the region of the calcar femorale, crossing trabeculae, similar to the appearance of an enchondroma or bone infarct, have been described in osteoporosis and osteoarthritis and probably represent unmasking of normally present reinforcing trabeculae. In ischemic necrosis, CT should be considered a useful modality for detection of early or mild alterations and may be valuable in treatment planning.

Noninvasive cerebrovascular assessment of Takayasu arteritis

BACKGROUND AND PURPOSE

Despite prominent neurological symptoms reported in Takayasu arteritis (TA), a complete evaluation of the cerebral circulation has not been consistently performed. The purpose of this study is to describe MR angiography (MRA), color Doppler flow imaging, and transcranial Doppler (TCD) findings in the extracranial and intracranial cerebral arteries in TA.

METHODS

MRA, color Doppler flow imaging, and TCD were performed in 21 patients with TA. Intima-media thickness was measured in the common carotid artery. The correlation between noninvasive studies and panaorto-arteriography was examined for supraortic vessels. Cerebral angiography findings were compared with the noninvasive methods in 7 patients. Intracranial hemodynamic changes detected by TCD were compared with extracranial circulation lesions assessed by panaorto-arteriography.

RESULTS

Noninvasive vascular techniques showed at least 1 abnormality in the extracranial and/or intracranial cerebral arteries in 20 of 21 patients (95%). Both MRA and color Doppler flow imaging showed a substantial correlation in the ability to detect obstructive lesions in supra-aortic vessels compared with panaorto-arteriography. High-resolution ultrasonography displayed common carotid artery wall thickening in 5 vessels that were considered normal by arteriography. In 24% of patients, MRA and TCD showed abnormalities consistent with stenosis of the basal cerebral arteries. In 10 patients with severe extracranial circulation involvement (detected by arteriography), TCD displayed intracranial hemodynamic changes consisting of dampened or blunted waveforms with low pulsatility.

CONCLUSIONS

The comprehensive assessment of cerebral circulation in TA patients by noninvasive methods allowed the detection of a high rate of diverse vascular abnormalities in both extracranial and intracranial circulation.

Vascular endothelial growth factor and hypertrophic osteoarthropathy

OBJECTIVE

Hypertrophic osteoarthropathy (HOA) is characterized by the coexistence of digital clubbing and periosteal proliferation of the tubular bones. Localized vascular proliferation associated with platelet/endothelial cell activation are recognized features of this syndrome. Current knowledge suggests that HOA develops from the presence in the systemic circulation of one or more growth factors that are normally inactivated in the lungs. The nature of these purported growth factors has not yet been identified. Vascular endothelial growth factor (VEGF) has several features that may fit in with the pathogenesis of HOA. The objective of our study was to measure serum and plasma levels of VEGF in different groups of patients with HOA.

METHODS

We studied 24 patients with HOA; of these, in 12 the HOA was secondary to cyanotic congenital heart disease and in 7 to lung cancer, while 5 represented primary cases. As controls we studied 28 individuals without HOA; of these, 12 were apparently healthy individuals, 7 had cyanosis secondary to chronic obstructive pulmonary disease, and 9 had lung cancer. ELISA was used to measure serum and plasma levels of VEGF.

RESULTS

Plasma levels of VEGF were significantly higher in the patients with primary HOA (median 46.2; range 19.4-398.8 pg/ml) and in those with lung cancer-HOA (median 75.5; range 24.6-166.7), compared to healthy controls (median 7.4; range: 0-26.1), p < 0.05. Serum VEGF levels were higher in patients with lung cancer and HOA (median 411.4; range 164.2-959.5 pg/ml) compared with lung cancer patients without HOA (median 74.5; range 13.2-205.4), p < 0.001.

CONCLUSIONS

Patients with primary HOA and those with HOA and lung cancer have increased circulating levels of VEGF. This cytokine may play a role in the pathogenesis of HOA.

Glycosylphosphatidylinositol-specific phospholipase D is expressed by macrophages in human atherosclerosis and colocalizes with oxidation epitopes

BACKGROUND

Glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) may play an important role in inflammation, because it can hydrolyze the GPI anchors of several inflammatory membrane proteins (eg, CD106, CD55, and CD59) and its hydrolytic products upregulate macrophage cytokine expression (eg, interleukin-1 and tumor necrosis factor-alpha). Because of its potential regulatory role in inflammatory reactions, we hypothesized that GPI-PLD might be expressed in atherosclerosis.

METHODS AND RESULTS

Immunohistochemistry using human GPI-PLD-specific rabbit polyclonal antiserum was performed on a total of 83 nonatherosclerotic and atherosclerotic human coronary arteries from 23 patients. Macrophages, smooth muscle cells, apoA-I, and oxidation epitopes also were identified immunohistochemically. Cell-associated GPI-PLD was detected in 95% of atherosclerotic segments, primarily on a subset of macrophages. Extracellular GPI-PLD was present in only 30% of atherosclerotic segments and localized to regions with extracellular apoA-I. In contrast, GPI-PLD was not detected in nonatherosclerotic segments. Expression of GPI-PLD mRNA by human macrophages was confirmed in vitro by reverse transcription/polymerase chain reaction. Further studies demonstrated that GPI-PLD-positive plaque macrophages contained oxidation epitopes, suggesting a link between oxidant stress and GPI-PLD expression. This possibility was supported by studies in which exposure of a macrophage cell line to H2O2 led to a 50+/-3% increase in steady-state GPI-PLD mRNA levels.

CONCLUSIONS

Collectively, these results suggest that oxidative processes may regulate GPI-PLD expression and suggest a role for GPI-PLD in inflammation and in the pathogenesis of atherosclerosis.

Intradermal tophi in gout: a case-control study

OBJECTIVE

To describe the characteristics of intradermal tophi in patients with gout and search for factors associated with their development.

METHODS

This is a case-control study of patients with gout: cases (Group A, n = 21) had intradermal (not subcutaneous) plaques of monosodium urate (MSU) crystals located in sites distant to articular or paraarticular structures, and controls (Group B, n = 42) had gout but no intradermal tophi. Both Group A and Group B were paired by sex, age (+/-5 years), and duration of the disease (+/-3 years). Analysis included serum and urinary uric acid levels at first visit, radiographic stage of gout, the presence of associated diseases, and previous therapy, specifically, chronic glucocorticoid and diuretic usage.

RESULTS

Intradermal tophi were located in the legs, forearms, buttocks, thighs, arms, and abdominal wall. Patients in Group A had a greater number of nonintradermal tophi in common sites (11.9+/-12.5 vs. 4.2+/-7.9, mean +/- SD; p = 0.018), decreased glomerular filtration rate (46.74+/-25.11 vs. 70.87+/-30.18 ml/min; p = 0.042), advanced radiographic changes (57.2 vs. 7.1%; p = 0.0001), and longterm glucocorticoid self-medication (76 vs. 36%; p = 0.006). We found no differences in other associated diseases between groups.

CONCLUSION

Intradermal tophi were commonly found in the legs and forearms, and less frequently in the buttocks, thighs, and abdominal wall of gouty patients, and were associated with longterm self-prescribed glucocorticoids and chronic renal failure. The occurrence of intradermal tophi in these patients appeared to correlate with advanced disease.

Orthostatic sympathetic derangement in subjects with fibromyalgia

OBJECTIVE

To assess the sympathetic-parasympathetic balance in individuals with fibromyalgia (FM), and its response to orthostatic stress, by power spectral analysis of heart rate variability.

METHODS

We studied 19 women with FM and 19 age matched controls. A high resolution electrocardiogram was obtained in supine and standing postures after achieving a stable heart rate. Spectral analysis of R-R intervals was done by the fast Fourier transform algorithm.

RESULTS

Analyses of the different frequency components revealed significant difference between the 2 groups in the low frequency (0.050-0.150 Hz) band, which reflects modulation of the sympathetic nervous system. Controls displayed an increased power spectral density upon standing (+0.081 +/- 0.217 Hz); individuals with FM had a discordant response (-0.057 +/- 0.097 Hz) (p = 0.018).

CONCLUSION

In FM, there is a deranged sympathetic response to orthostatic stress. This abnormality may have implications regarding the pathogenesis of FM.

Absence of ANCA in Mexican patients with Takayasu's arteritis

Antineutrophil cytoplasmic autoantibodies (ANCA) were sought in 43 sera from 39 Mexican patients with typical Takayasu's arteritis (TA), (5 with active and 34 with inactive disease), and in a comparative group comprising 50 sera. Results were negative in all cases. This suggests that ANCA are not a serologic feature in TA per se, even during its active stage. ANCA positivity in TA, when present, may be a non-related phenomenon and probably identifies a subset of patients with atypical forms of TA or a polyangiitis overlap syndrome.

Ankylosing spondylitis is indigenous to Mesoamerica

OBJECTIVE

Paleopathology helps to define the origin and the migration of diseases. It has been established that genetic and environmental factors play a role in the pathogenesis of ankylosing spondylitis (AS). We investigated whether AS was present in Mesoamerica before contact with the European civilization.

METHODS

We studied the collection of Mesoamerican human skeletal remains preserved at the National Museum of Anthropology of Mexico, searching for features of AS.

RESULTS

We found one incomplete specimen of a man of the Postclassic period (900-1521 AD). It showed fusion of the vertebral column from T8 to L5 due to ankylosis of the apophyseal joints and of the spinal processes. The pelvis was not preserved. Radiographs demonstrated ossification of both supraspinous and interspinous ligaments.

CONCLUSION

Our findings suggest AS was present in Mesoamerica before the arrival of Europeans.

Evidence of hypertrophic osteoarthropathy in human skeletal remains from pre-Hispanic Mesoamerica

Hypertrophic osteoarthropathy is one of the earliest recognized disease entities in the history of medicine. It has a peculiar periosteal proliferation distinctive from other bone diseases. In its advanced stage, it leaves an indelible mark on the skeleton. It has been recently shown that digital clubbing is accompanied by a bone remodeling process of the underlying phalanges. Thus, theoretically, this entity can be recognized in ancient human skeletal remains. We studied part of the collection of skeletal remains from pre-Hispanic Mesoamerica preserved at the National Museum of Anthropology of Mexico City. We examined 1000 specimens and found 2 skeletons with widespread, bilateral, symmetric periosteal proliferation of the tubular bones in addition to the bone remodeling changes of the distal phalanges. One of the specimens was from the Formative period (2000 B.C. to 100 A.D.). We conclude that hypertrophic osteoarthropathy can be recognized in ancient human skeletal remains and that this disease was present in Mesoamerica near the time of the original description of clubbing by Hippocrates about 2500 years ago.

Primary hypertrophic osteoarthropathy: another heritable disorder associated with patent ductus arteriosus

Patent ductus arteriosus (PDA) is a congenital malformation that has been linked to diverse heritable and chromosomal disorders. Primary hypertrophic osteoarthropathy (HOA) is a rare heritable syndrome in which digital clubbing and periostosis become evident without any underlying illness. The objective of this article is to describe four patients with coexisting PDA and primary HOA. Surgical closure of the ductus showed no effect on the skeletal changes. Primary HOA should be included among the heritable disorders that may be associated with PDA.

Diagnostic imaging in hypertrophic osteoarthropathy

This review discusses our experience with conventional radiography and advanced imaging techniques in the evaluation of diverse soft tissue, skeletal and joint abnormalities frequently observed in patients with both the primary and secondary forms of hypertrophic osteoarthropathy. The manifestations include finger clubbing, elephant feet, cutis verticis gyrata, synovial effusion, periostosis, tuftal hypertrophy and acro-osteolysis. Its coexistence with other skeletal and joint diseases and its imaging differential diagnosis are also reviewed.

New clinical and radiographic features of the seronegative spondyloarthropathies

This article reviews new data supporting the hypothesis that the clinical spectrum of the seronegative spondyloarthropathies is wider than previously realized. It describes the literature in general and specific reports on the prevalence and clinical features of seronegative spondyloarthropathies in a number of different populations from America and Asia. Undifferentiated or unclassified spondyloarthropathies are now recognized more frequently. There is an extensive analysis of new proposals for nomenclature and criteria for classification that need to be validated. The normal appearance and biomechanics of the sacroiliac joints as well as new imaging techniques to approach them in several diseases are also discussed. Clinical, radiographic, and histopathologic findings in spinal disease and further observations on gut inflammation and intestinal permeability are also presented here. A long list of clinical associations of the seronegative spondyloarthropathies is also given.

Takayasu's arteritis in children

We reviewed the clinical features of 26 children with Takayasu's arteritis. In contrast to what is often seen in adults, in this age group inflammation of different systems is a conspicuous feature. Eighty five percent of cases had arterial hypertension. The high incidence of arthritis and heart failure provoked confusion with rheumatic fever. There was a high frequency of positive purified protein derivative (73%) and lymphadenopathy (38%) with a histological picture of caseating granulomas, suggesting a link between Takayasu's arteritis and an atypical mycobacterial infection. No improvement of the arterial obstruction was observed with corticosteroid therapy. Takayasu's arteritis in children presents as an aggressive often lethal disease. The mortality rate was 35% over an observation period of 5 years.

The spectrum of soft tissue and skeletal abnormalities of hypertrophic osteoarthropathy

We review our radiographic experience with hypertrophic osteoarthropathy. Soft tissue abnormalities such as finger clubbing, "elephant feet" and cutis verticis gyrata are well appreciated by plain radiography. Hypertrophic osteoarthropathy is characterized by a bone remodeling process at the tip of the digits. In older patients it is manifested as tuftal hypertrophy whereas in younger individuals acroosteolysis takes place. Radiographic signs of inflammatory arthropathy are conspicuously absent. Periosteal proliferation is an orderly evolving process in 3 dimensions: in the number of affected bones, in the area of involvement of a given bone and in the shape of periostitis.

Digital clubbing: a numerical assessment of the deformity

We describe a simple method that defines with numbers the drumstick deformity of the digits. We measured 2 circumferences on each of the 10 fingers at the nail bed (NB) and at the distal interphalangeal joint (DIP), the sum of the 10 ratios NB:DIP was termed Digital Index. Intraobserver variation of the Digital Index was small, with a Pearson's correlation coefficient of R = 0.979; interobserver variation was also not significant (R = 0.999). Making use of this Digital Index, we studied 22 patients with digital clubbing associated with cyanotic congenital heart disease and 66 healthy controls. Digital Index clearly separated patients from controls, 10.73 +/- 0.32 vs 9.33 +/- 0.27 (means +/- SD). The Index was independent of age or sex. Patients with hypertrophic osteoarthropathy had significantly higher indices than patients with clubbing alone.

CT analysis of proximal femoral trabecular pattern simulating skeletal pathology

The proximal femoral trabecular pattern was studied in 20 patients, six cadavers, and 20 macerated specimens using plain film radiography and CT. A distinctive pattern of increased radiodensity in the proximal femur is described in patients and specimens with osteoporosis and osteoarthritis. The appearance is similar to that of an enchondroma or bone infarct. This pattern may be explained by biomechanical principles and is created by unmasking or hypertrophy of preexistent, reinforcing trabeculae. Confusion with osseous pathology can be avoided if the radiologist is aware of this pattern.

Primary hypertrophic osteoarthropathy

We describe seven patients with primary HOA and review 125 cases reported in the English, French, and German literature. The salient clinical features of primary HOA are: a bimodal distribution of disease onset with one peak during the first year of life and the other at age 15, a male predominance (nine to one), uncommon benign joint effusion, and a variety of skin abnormalities resulting from cutaneous hypertrophy or glandular dysfunction. We concluded that HOA is not a synovial disease. It is suggested that synovial effusions, when present, are perhaps a sympathetic reaction to the neighboring periostitis. Proposed diagnostic criteria for HOA, including digital clubbing and radiographic periostitis, appear 86% sensitive. The clinical features, age of onset, and sex distribution suggest that a genetically controlled growth promoting factor, different from growth hormone, plays a role in the pathogenesis of this syndrome.