Wearing face masks while climbing stairs influences respiratory physiology

BACKGROUND

During the COVID-19 pandemic wearing face masks was mandatory. Nowadays, face masks are still encouraged indoors, especially in hospitals. People climbing stairs with masks describe unpredictable dyspnea.

METHODS

Healthy adults climbed 5 floors with and without a mask. Various cardio-respiratory parameters were measured, including O2-Saturation (O2-Sat) and End-tidal CO2 (EtCO2), at baseline and on the top floor. Subjective indexes, such as Borg's scale, were evaluated.

RESULTS

Thirty-two volunteers (16 males), median age 39 years (IQR 32.5-43), median BMI=23.6 (IQR 21.5-25.1), with good fitness levels, participated. Comparing baseline to end-activity, median (IQR): O2-Sat change was -1.0% (-2-0) without mask, versus -3.0% (-4-0) with mask, p=0.003; EtCO2 +7.0 (+3.3-+9) without mask, versus +8.0 (+6 -+12) with mask, p=0.0001. Hypercarbia was seen in 5 (15.6%) participants without mask, median=48mmHg (IQR 47.5-51), and in 11 (34%) participants with mask, median=50mmHg (IQR 47-54), p<0.001. Desaturation (O2-Sat<95%) was seen in 5 (15.6%) participants without mask, median=94% (IQR 93-94%), and in 10 (31%) participants with mask, median=91.5% (IQR 90-93%), p=0.06. Regression analysis demonstrated that only male sex was significantly associated with abnormal EtCO2 (OR=26.4, 95%CI=1.9-366.4, p=0.005). Ascent duration increased from median (IQR) of 94 seconds (86-100) without mask to 98 seconds (89-107) with mask, p<0.001. Borg's scale of perceived exertion (range 0-10) increased from median (IQR) of 3.0 (2.5-3.87) without mask to 4.0 (3.0-4.37) with mask, p<0.001.

CONCLUSIONS

During routine daily activities, such as stair-climbing, face masks cause dyspnea, and have measurable influences on ventilation, including true desaturation and hypercapnia, especially in males.

Pulmonary Evaluation in Children with Post-COVID-19 Condition Respiratory Symptoms: A Prospective Cohort Study

Background: Studies on post-COVID-19 condition (PCC) in adults have shown deterioration in pulmonary function tests (PFTs), mainly a diffusion limitation. Among the pediatric population, data are scarce. Aim: To characterize PFTs in children with PCC, including changes over time. Methods: A prospective longitudinal study of children with defined PCC and respiratory complaints who were referred to a designated multidisciplinary clinic from 11/2020 to 12/2022. Results: Altogether, 184 children with a mean age of 12.4 years (SD 4.06) were included. A mild obstructive pattern was demonstrated in 19/170 (11%) at presentation, as indicated by spirometry and/or positive exercise challenge test and/or reversibility post bronchodilators, only three had a previous diagnosis of asthma. Lung volumes and diffusion were normal in all but one patient (1/134, 0.7%). Exhaled nitric oxide levels were elevated in 32/144 (22%). A total of 33 children who had repeated PFTs had normal or near-normal PFTs on follow-up testing, including seven (21.2%) who had mild obstructive PFTs at presentation. Multivariate analysis identified older age [OR 1.36 (95% CI:1.07-1.75)], specific imaging findings (prominent bronchovascular markings (OR 43.28 (95% CI: 4.50-416.49)), and hyperinflation (OR 28.42, 95% CI: 2.18-370.84)] as significant predictors of an obstructive pattern on PFTs. Conclusions: In children with PCC and respiratory symptoms, the most common impairment was a mild obstructive pattern; most were without a history of asthma. Improvement was witnessed in long-term follow-up. In contrast to the adult population, no diffusion limitation was found. Empirical periodic inhaler therapy may be considered in children with factors associated with PFT abnormalities.

Prognostic significance of granulomas in children with Crohn's disease

OBJECTIVES

Granulomas have long been considered the histological hallmark of Crohn's disease (CD). Currently, there is considerable dispute with regards to their prognostic implications. We aimed to determine the effect of granulomas on phenotypic features and disease's long-term outcomes in a large cohort of pediatric CD patients.

MATERIALS AND METHODS

Medical records of pediatric CD patients diagnosed at the Schneider Children's Medical Center were reviewed retrospectively. Patients were categorized into two groups based on the presence or absence of granulomas at diagnosis. Baseline characteristics included anthropometric, clinical, laboratory, radiological and endoscopic data. Outcome measures included flares, hospitalizations, biological therapy and surgery.

RESULTS

Of 289 CD patients diagnosed between 2001 and 2015, 99 patients (34%) had granulomas. Median age of the entire cohort at diagnosis was 14.2 years (females, 42.6%), with a median follow-up of 8.5 years. Patients with granulomas had a significantly higher percentage (47.5% vs. 23.7%, p = .001) of upper gastrointestinal involvement and ileo-colonic disease (64.9% vs. 49.5%, p = .01). Extraintestinal manifestations were twice as common in patients without granulomas (16.3% vs. 8.1%, p = .05). Patients with granulomas were more likely to be hospitalized (HR =1.43, 95% CI: 1.0-2.0) and to receive biologic therapy (HR = 1.52, 95% CI: 1.1-2.11). Additionally, both of these disease outcomes occurred significantly earlier (p = .013 and p = .027, respectively). In contrast, patients with granulomas did not exhibit increased risk of flares or bowel resection.

CONCLUSION

Patients with granulomas exhibited a distinct phenotype at diagnosis and demonstrated a more severe disease course.

Why are some species more commonly afflicted by arthritis than others? A comparative study of spondyloarthropathy in primates and carnivores

Spondyloarthropathy is a painful arthritic affliction of humans that also occurs in wild mammals. Important questions remain concerning the underlying causes of spondyloarthropathy in mammals, particularly regarding whether it is infectious in origin or driven by genetic predisposition and environmental stressors. Moreover, spondyloarthropathy has negative effects on host fitness, leading to potential conservation concerns if it impacts threatened species. Using a comparative data set on the prevalence of joint disease in 34 primate species and 100 carnivore species, we tested predictions involving the epidemiological correlates of spondyloarthropathy in wild mammals. Analyses revealed that 5.6% of primates and 3.6% of carnivores exhibited signs of spondyloarthropathy, with maximum incidence as high as 22% in great apes and 27% in bears. We tested whether prevalence of spondyloarthropathy increases with population density and group size, greater contact with soil, a slower host life history, increased ranging, dietary factors and body mass. We found general support for an effect of body mass, with larger bodied primates and carnivores exhibiting a higher prevalence of spondyloarthropathy. In addition, more threatened species experienced higher rates of spondyloarthropathy, with this association influenced by body mass and phylogeny. The effect of body mass could reflect that larger animals are exposed to more pathogens through greater consumption of resources, or that joints of larger bodied mammals experience greater biomechanical stresses, resulting in inflammation and activation of local joint infections.

Contributions of paleorheumatology to understanding contemporary disease

As paleopathology has evolved from observational speculation to analysis of testable hypotheses, so too has recognition of its contribution to vertebrate paleontology. In the presence of significant structural and density variation (between matrix and osseous structures), x-rays provide an additional perspective of osseous response to stress and disease. As film techniques are time and cost expensive, fluoroscopy has proven a valuable alternative. Radiologic techniques also allow non-invasive "sectioning" of specimens, illustrating significant internal detail. The object can be "split" on a plane and the two portions rotated to "open" the image. This three-dimensional approach now can be applied to other forms of sequential data to their facilitate 3-dimensional representation graphically or with solid representations. Antigen and microstructure may be well preserved in fossils. Molecular preservation with retention of helical structure and sensitivity to collagenase has been demonstrated in 10,000 year old collagen. Antigen has been extracted from 100 million year old bone and documented, in situ, in 11,000 year old bone. If the appropriate site in the tissue is assessed, if antigen is still present, and if the appropriate antisera is utilized, fixation of the antibody to the specimen can be detected. Minute amounts of DNA can be amplified and analyzed. Recovery of DNA from a 40,000 year old mammoth, 17,000 year old bison and from 25 million year old insects provides opportunity for cloning and independent assessment of relationships. Implications of available technology focuses direction for development of collaborative approaches.

[Clues to recognition of kidney disease in archaeologic record: characteristics and occurrence of leontiasis ossium]

The possible osseous effect of kidney dysfunction was evaluated in a modern skeletal population for future use in assessment of archaeologic samples. Frequency and distribution on the bones of cysts, articular surface alterations, subperiosteal resorption, porosity, osteochondritis, digital tuft alteration and periosteal reaction were recorded in 94 individuals with known kidney failure in the Hamann-Todd collection. Independent radiologic analysis was also pursued. The results were compared with a control sample. The pattern of joint surface alteration and periosteal reaction may facilitate recognition of chronic renal disease in the osseous record. Subtle manifestations of leontiasis ossium are present in the form of cranial thickening and increased cranial size and weight, but teeth spacing are rare. Pseudo osteomatous lesions are common. This study perhaps explains the apparent rarity of actual leontiasis ossium.

American College of Rheumatology--63rd annual meeting. 13-17 November 1999, Boston, MA, USA

The 63rd National Scientific Meeting of the American College of Rheumatology was quite general in scope, with clinical and animal model studies forming the basis for this report. Arthritis-suppressive medications were further analyzed as to morbidity and effect on disease progression. Biological therapy was an important topic. Intervention for gastroprotection, osteoarthritis, spondyloarthropathy, lupus, osteoporosis and antiphospholipid antibodies, was especially explored.

Dose-loading with hydroxychloroquine improves the rate of response in early, active rheumatoid arthritis: a randomized, double-blind six-week trial with eighteen-week extension

OBJECTIVE

To investigate the usefulness of hydroxychloroquine (HCQ) dose-loading to increase the percentage of responders or rate of response in treating rheumatoid arthritis (RA).

METHODS

Two hundred twelve patients with early RA (mean duration 1.5 years) were enrolled in a 24-week trial. Patients were stabilized with 1,000 mg naproxen/day and then began a 6-week, double-blind trial comparing treatment with HCQ at 400 mg/day (n = 71), 800 mg/day (n = 71), and 1,200 mg/day (n = 66), followed by 18 weeks of open-label HCQ treatment at 400 mg/day.

RESULTS

All patients had mild, active disease at the time of initiation of HCQ treatment (31-43% rheumatoid factor positive; no previous disease-modifying antirheumatic drugs; mean swollen joint count 8.6-10.4). Based on the Paulus criteria, response during the 6-week double-blind portion of the study was 47.97%, 57.7%, and 63.6% in the 400 mg/day, 800 mg/day, and 1,200 mg/day groups, respectively (P = 0.052). Discontinuations for adverse events were dose related (3 in the 400 mg/day group, 5 in the 800 mg/day group, 6 in the 1,200 mg/day group). Most involved the gastrointestinal (GI) system, with the background naproxen treatment possibly contributing. Ocular abnormalities occurred in 17 of 212 patients (8%) but were not dose related.

CONCLUSION

Dose-loading with HCQ increased the degree of response at 6 weeks in this group of patients with early, predominantly seronegative RA. Adverse GI events were dose related, while adverse ocular events were not.

Dose-loading with hydroxychloroquine improves the rate of response in early, active rheumatoid arthritis: a randomized, double-blind six-week trial with eighteen-week extension

OBJECTIVE

To investigate the usefulness of hydroxychloroquine (HCQ) dose-loading to increase the percentage of responders or rate of response in treating rheumatoid arthritis (RA).

METHODS

Two hundred twelve patients with early RA (mean duration 1.5 years) were enrolled in a 24-week trial. Patients were stabilized with 1,000 mg naproxen/day and then began a 6-week, double-blind trial comparing treatment with HCQ at 400 mg/day (n = 71), 800 mg/day (n = 71), and 1,200 mg/day (n = 66), followed by 18 weeks of open-label HCQ treatment at 400 mg/day.

RESULTS

All patients had mild, active disease at the time of initiation of HCQ treatment (31-43% rheumatoid factor positive; no previous disease-modifying antirheumatic drugs; mean swollen joint count 8.6-10.4). Based on the Paulus criteria, response during the 6-week double-blind portion of the study was 47.97%, 57.7%, and 63.6% in the 400 mg/day, 800 mg/day, and 1,200 mg/day groups, respectively (P = 0.052). Discontinuations for adverse events were dose related (3 in the 400 mg/day group, 5 in the 800 mg/day group, 6 in the 1,200 mg/day group). Most involved the gastrointestinal (GI) system, with the background naproxen treatment possibly contributing. Ocular abnormalities occurred in 17 of 212 patients (8%) but were not dose related.

CONCLUSION

Dose-loading with HCQ increased the degree of response at 6 weeks in this group of patients with early, predominantly seronegative RA. Adverse GI events were dose related, while adverse ocular events were not.

Reactive arthritis and Reiter's syndrome

Reactive arthritis is an important source of morbidity. It is acquired through infectious agent diarrhea (food poisoning) or from sexual contact. Recognition is important because it allows a therapeutic approach that usually results in improvement of quality of life.

Reflex sympathetic dystrophy

Reflex sympathetic dystrophy, causalgia, Sudeck's atrophy, shoulder-hand syndrome, and transient osteoporosis represent a spectrum of sympathetic disturbances which typically present with regional findings. They are often pauciarticular in distribution and uniquely sensitive to timely therapeutic intervention and to preventative measures. Clinical and radiologic appearances are quite characteristic. Thermographic examination provides a valuable tool for monitoring the therapeutic response. The major factor in therapeutic efficacy is aggressive physical therapy. Although therapeusis has been facilitated by a multitude of agents, therapeutic resistance is unfortunately the circumstance, when intervention is delayed.

Avascular Necrosis: Occurrence in Diving Cretaceous Mosasaurs

A study of vertebrae of extinct giant marine lizards showed the presence of avascular necrosis in two of the three most common genera of these mosasaurs, Platecarpus and Tylosaurus. This bone disease was invariably present (involving 5 to 66% of vertebrae) in these genera, but absent in a third genus Clidastes. Differential occurrence of avascular necrosis may be related to decompression syndrome, suggesting different habitat and diving habits of the respective genera.

Lymphadenopathy and lymph node infarction in the course of gold therapy

Lymphadenopathy, as a complication of gold therapy, appears to be an uncommon occurrence. Lymph node infarction has not been previously documented in this setting. The unique pathologic features in this case may reflect: a phenomenon specific to gold; early examination of the infarcted node; or underlying leukocytoclastic angiitis secondary to gold toxicity. Polymorphonuclear leukocytic infiltration of an infarcted lymph node has apparently not been previously reported.

Perturbation of fibrinolysis inhibitors in progressive systemic sclerosis

Significance of fibrinolysis in pathophysiology of progressive systemic sclerosis (PSS) has been the subject of much speculation. Renal disease in PSS was associated with significant depression of an inhibitor of fibrinolysis, antithrombin III (ATIII), independent of general disease activity. Association of ATIII depression with plasminogen consumption supports an active role for plasmin or another ATIII-inhibitable enzyme in the pathophysiology of renal disease in PSS, and may explain the thrombotic tendency and propensity for fibrin deposition.

Collagen-vascular diseases

Some of the collagen-vascular diseases and overlap syndromes included are polymyosititis, systemic lupus erythematosus, scleroderma, Sjögren's syndrome, and Raynaud's phenomenon. Because diagnosis and treatment can be complicated, primary care physicians may want to seek experienced consultation.

Vasculitis

Vasculitis is reviewed as a continuum of disease from asymptomatic to life-threatening. Therapeutic intervention predicated upon assessment of the significance of organ system involvement and the relative risks of the various forms of therapeutic intervention are discussed.

Objective assessment with establishment of normal values for lumbar spinal range of motion

The purpose of this article is to present an assessment method, in conjunction with age-related normal values, for lumbar spinal range of motion. Lumbar flexion, lumbar extension, and right and left lateral flexion were measured on 172 subjects by a combination of goniometry and spinal distraction techniques. Normal values are given for six age groups; each group had a range of 10 years. The results demonstrate that a significant decrease in lumbar spinal range of motion is expected with increasing age. The interobserver reliability based on 17 subjects was substantial for the four measurements taken; coefficients ranged from +.76 to +1.0. The information may prove useful to the clinician as an improved method for assessing the lumbar spine.

Appendix: a model of plaque formation

Equations describing plaque formation in soft agar have been based on certain simplifying assumptions, for which data are presented. The derived equations permit one to calculate (i) average plaque size as a function of the initial density of indicator cells (Do), (ii) the number of cells lysed per plaque as a function of Do, and (iii) the cumulative number of cells lysed at various stages of plaque development. The calculated values agree well with those determined experimentally.

Beware of the normal excretory urogram

Excretory urography is not an infallible diagnostic procedure and should not be relied upon exclusively. A normal study must never result in the rejection of additional data derived from history, physical examination and laboratory tests. Two case histories are presented to underscore this caveat. Excretory urography must be supplemented additional radiographic evaluations when the conventional study fails to completely explain the clinical situation.