Life-threatening purpura and vasculitis

Discordance between data acquired by history and findings of physical examination: a phenomenal paradox

BACKGROUND

History and physical examination are the basis of any diagnosis. The findings of the physical examination usually corroborate the thoughts generated by the medical history. However, it is not uncommon for the physician to note discrepancies between the history and the physical examination.

METHODS

Two physicians provided a list of diseases they have encountered in which there is occasionally discordance between the data retrieved from the patient's medical history and the findings of the physical examination. To verify the data from knowledge and experience, we resorted to two main medical textbooks and relevant articles from PubMed.

RESULTS

We identified 25 diseases where a discordance between history and physical examination may frequently be observed. These diseases cover a wide spectrum of systems (i.e., neurological, cardiological, respiratory, and gastrointestinal).

DISCUSSION

A variety of diseases are associated with a discordance between the findings one might expect based on the medical history and the actual findings of the physical examination. Physicians need to be aware of this paradox, as misdiagnosis can be detrimental in some of these diseases. We acknowledge that this is just a sample, and not an exhaustive list, of all diseases with such a discordance.

The importance of myeloid-derived suppressor cells in the regulation of autoimmune effector cells by a chronic contact eczema

Induction of a chronic eczema is a most efficient therapy for alopecia areata (AA). We had noted a reduction in regulatory T cells during AA induction and wondered whether regulatory T cells may become recruited or expanded during repeated skin sensitization or whether additional regulatory cells account for hair regrowth. AA could not be cured by the transfer of CD4(+)CD25(high) lymph node cells from mice repeatedly treated with a contact sensitizer. This obviously is a consequence of a dominance of freshly activated cells as compared with regulatory CD4(+)CD25(+) T cells. Instead, a population of Gr-1(+)CD11b(+) cells was significantly increased in skin and spleen of AA mice repeatedly treated with a contact sensitizer. Gr-1(+)CD11b(+) spleen cells mostly expressed CD31. Expression of several proinflammatory cytokines as well as of the IFN-gamma receptor and the TNF receptor I were increased. Particularly in the skin, Gr-1(+) cells expressed several chemokines and CCR8 at high levels. Gr-1(+)CD11b(+) cells most potently suppressed AA effector cell proliferation in vitro and promoted partial hair regrowth in vivo. When cocultured with CD4(+) or CD8(+) cells from AA mice, the Gr-1(+)CD11b(+) cells secreted high levels of NO. However, possibly due to high level Bcl-2 protein expression in AA T cells, apoptosis induction remained unaltered. Instead, zeta-chain expression was strongly down-regulated, which was accompanied by a decrease in ZAP70 and ERK1/2 phosphorylation. Thus, a chronic eczema supports the expansion and activation of myeloid suppressor cells that, via zeta-chain down-regulation, contribute to autoreactive T cell silencing in vitro and in vivo.