Web-based questionnaires to capture acute infections in long-term cohorts

Background

Incidence of acute respiratory infections (ARI) and gastrointestinal infections (GII) are difficult to assess due to high frequency episodes, limited severity and short duration. Retrospective assessments therefore are particularly prone to recall bias, while prospective assessment with conventional questionnaires requires high discipline from participants which is difficult to maintain over longer time periods. Web-based questionnaires (WQ) allow integration of a recall system and thus carry the potential to prospectively capture acute infections. We investigated the feasibility of a weekly WQ assessing symptoms of ARI and GII among participants of the German National Cohort (GNC).

Material and methods

In the study centres Hamburg and Bremen of the GNC participants of the Pretest 1 phase (September to November 2011) were invited to additionally take part in this feasibility study testing the WQ. Every Monday participants received an e-mail, containing a link to the WQ, asking for occurrence of ARI or GII symptoms during the past 7 days. The study took place from the beginning of February until mid-July 2012. We calculated the overall proportion of participation, weekly participation and the number of weekly reports per participant and we estimated incidences of ARI, ILI and GII.

Results

Of 200 Pretest 1 participants 171 (86?%) reported having an email address and thus were eligible for the web-based study. A total of 167 (98?%) agreed to participate. Participants of the web-based study were younger and better educated than non-participants. Access to Internet decreased with increasing age. Of the 167 participants in the feasibility study, 144 (86?%) responded at least once during the study period of 23 weeks, 5 persons (3?%) had non-functioning email addresses and 18 (11?%) did not respond at all. The weekly response varied between 62?% and 81?%, the median was 74?% (IQR: 71–77?%). Weekly median reports per person were 20 (IQR: 14–22; range 1–23). More than 90?% of participants responded during the first 3 days. The following mean incidence rates were found: ARI, 12?%; ILI, 0.49?%; and GII, 3?%.

Conclusion

Use of WQ in prospective studies seems well possible, as Internet access is frequent among study participants and major technical problems did not occur. We observed high participation during the study period of 6 months and low drop out numbers. Participants of the web-based study were slightly younger and better educated than non-participants, so selection bias is possible and must be kept in mind when discussing generalizability of the results.     

Clinicopathologic Study of Cutaneous Plasmacytoma

Eight patients with skin tumor lesions composed of dense, predominantly plasma cell infiltrates were studied. Primary cutaneous plasmacytoma can be reactive (polyclonal) or neoplastic (monoclonal). In four of the patients skin lesions were associated with multiple myeloma. Specific skin lesions usually consisted of reddish or purple nodules located on the trunk. In one case the cutaneous lesions developed at the site of previous herpes zoster. Histologically, the cutaneous plasmacytic infiltrate was mainly diffuse and monomorphous. Most of the plasma cells were mature, but in some cases immature immunoblasts and mitoses were observed. Serum immunoelectrophoresis findings correlated with the monoclonality or polyclonality of the plasmacytoma. Presence or absence of systemic involvement cannot be predicted from the appearance of clinical lesions or from maturity of plasma cell infiltration in the skin.     

Skin Zinc Concentrations in Patients with Varicose Ulcers

The concentration of zinc in the skin has been determined noninvasively in patients with varicose vein ulcers. The examinations were performed with the use of diagnostic x-ray spectrometry, a method based on x-ray fluorescence for in vivo noninvasive evaluation of trace elements. Four skin foci were examined: at the periphery of the ulcer and control areas in a nonulcerated area in the diseased leg, in the noninvolved leg, and in the proximal inner surface of the arm. Zinc levels around the ulcer (mean +/- SD, 9.8 +/- 4.0 micrograms of zinc in 1 g of wet tissue) were higher than those in the nonulcerated skin in the diseased leg (6.9 +/- 3.0 micrograms/g, p greater than 0.05) and those in the noninvolved leg (5.4 +/- 2.0 micrograms/g, p less than 0.01). The concentration of zinc in the inner proximal surface of the arm (9.8 +/- 2.8 micrograms/g) was significantly higher than those of a control group (5.3 +/- 1.9 micrograms/g, p less than 0.01). These results suggest a defect of zinc distribution in patients with varicose vein ulcers.     

Dissemination in Cutaneous Leishmaniasis

In a field study of cutaneous leishmaniasis (CL) due to Leishmania major, zymodeme Lon-4, in an endemic focus in Saudi Arabia, 80 patients in a group of 643 patients (12.44%) were found to have multiple, inflammatory, satellite papules (SP) around one or more CL lesions. The SP often appeared to erupt after commencement of antileishmanial treatment. They showed a range of morphology and pathology, and comparisons with corresponding CL lesions showed important differences. Amastigotes were seen in only one of seven biopsy specimens. Another morphologic feature, subcutaneous induration (SCI), was noted on routine palpation in 20 patients in the same patient group (3.11%). The SCI either was radiating all around the lesion and appeared as an "iceberg nodule" or was present as a "tonguelike" process proximal to the CL lesion. Amastigotes were seen in four of nine biopsy specimens of SCI. SP and SCI represent reactions to local dissemination of the parasite or its antigenic products, and as morphologic features aid in the clinical diagnosis of CL.     

REACTION IN LEPROSY: ACUTE PHASE REACTANT RESPONSE DURING AND AFTER REMISSION

Sera from 25 patients with type 1 (Lepra), upgrading and downgrading, and type 2 (erythema nodosum leprosum [ENL]) reactions were assayed, during the reaction and after its clinical remission, for changes in levels of alpha-1-antitrypsin (A1A) and C-reactive protein (CRP). The results were compared with those from normal healthy adults and patients of leprosy without history and/or clinical evidence of reaction. The A1A levels correlated better with changes in status of type 1 reaction; whereas CRP levels correlated well with alterations in type 2 reactions and were definitely superior to A1A in this situation for monitoring the course of these episodes.     

Clinical correlations and prognosis based on hyaluronic acid serum levels in patients with progressive systemic sclerosis

The serum levels of hyaluronic acid (sHA) were measured using an affinoimmunoenzymatic assay in patients with distal (n = 16) and proximal (n = 15) progressive systemic sclerosis (PSS) and in 31 controls. The severity of PSS was evaluated using a standardized organ-involvement score. The mean sHA was significantly higher in the patients with PSS than in controls (mean +/- SD:80 +/- 43.4 micrograms/l vs. 42.3 +/- 19.1 micrograms/l, P less than 0.001). sHA was significantly higher in patients with proximal PSS than in patients with distal PSS (106.4 +/- 44.6 micrograms/l vs. 55.4 +/- 23.8 micrograms/l, P less than 0.001). A positive correlation was found between sHA and the disease score (r = 0.67, P less than 0.001). sHA was also correlated with lung diffusion capacity for carbon monoxide (r = 0.70, P less than 0.001), but only in the those patients who had abnormal lung function, and therefore presumably had lung PSS involvement. We suggest that sHA could be an indicator of the degree of systemic involvement in PSS. Its prognostic value and possible use in the follow up of patients with PSS remain to be clarified.