PART II
DIAGNOSTICS OF TROPICAL DISEASES
CHAPTER XLIII
DIAGNOSTIC PROBLEMS AND PROCEDURES TOGETHER WITH COSMOPOLITAN DISEASES IN THE TROPICS
In temperate climates we always keep in mind syphilis, tuberculosis and the pyogenic infections when a diagnosis is in question. In the tropics these conditions are just as common, if not more so, and added to them we have many other diseases with protean manifestations such as malaria, beriberi, leprosy, ancylostomiasis and other helminthic infections, pellagra and amoebiasis.
The common mistake made by the physician when he first arrives in a tropical country is to expect to deal chiefly with diseases designated tropical. Before going to any tropical country the most important preparation is the study of the statistical reports from that section, covering a number of years. Everyone taking up the study of tropical disease should first study the geographical distribution of such diseases and those practising in temperate climates should remember that the first question to be asked a man suspected of having a tropical disease is “Where have you been during the past months and years?” Then too the same question should be applied as to intimate associates of the patient.
We all know how rare it is in temperate climates to find definite pathological conditions in people who are apparently well. In such people a definite finding of a cause sufficient to account for an illness is usually the key to the diagnosis. With those from the tropics, however, it is different. A single individual may be found upon examination to have amoebiasis, malaria, filariasis and syphilis, yet none of these infections prevent him from following his usual occupation. When such a patient comes to a ward it requires a correlating mind to eliminate four or five definite diagnoses, and fix upon some disease which is common to both tropics and temperate climates, as for example, typhoid fever.
In diagnosis in the tropics it is necessary to have at one’s fingers’ ends the various physical signs and subjective symptoms more or less characteristic of every disease of man as well as the laboratory findings. It is only when one has at hand all obtainable information that the solution of the medical problem becomes possible.
Furthermore, it is necessary to be familiar with the fact that certain infections, which at times give rise to marked alterations in the health of a patient, may at other times, and in particular when different races of man are concerned, give rise to no recognizable interference with health. This is particularly true of certain helminthological diseases, as for instance the slight effects often noted in hookworm infection in the African races as against the marked damage to those of the white race harboring such parasites.
While the medical man is apt to have superabundant energy during the first few months of his tropical service this later gives way to the opposite state and in particular to a lack of initiative. It is possible to do that which is absolutely demanded in the daily work, but this is along the lines of routine requirements and to the exclusion of new and difficult methods of diagnosis.