Pseudo food allergy

Why Do People Misdiagnose Themselves with Food Hypersensitivity? An Exploration of the Role of Biopsychosocial Factors

Up to 35% of people self-diagnose food allergy or intolerance (food hypersensitivity [FH]), or diagnose it in their child, and self-manage the condition rather than seek a clinical diagnosis. This is much higher than the latest FH prevalence rate, estimated to affect 2–5% of the general population. The actual prevalence rate may be underestimated due to the lack of diagnostic services; however, this can only account for a small proportion of the discrepancy because only a small percentage of self-reported FH can be clinically confirmed. Many people are therefore misdiagnosing their or their child’s symptoms as FH and needlessly removing foods from their or their child’s diet. There are a number of possible reasons for this misdiagnosis, which can be considered from a biopsychosocial perspective. Psychological factors include a confusion over the diagnosis, coincidental pairing of food and symptom, psychological or psychosomatic reactions, and taste aversions. There are also biological mechanisms that have not been fully considered in food allergy research that may be relevant, such as conditioning of the immune system or stress responses. A social context pertains to a greater awareness of FH due to media coverage and changes in food labelling laws. Any of these theories are plausible, but the research to date has a number of methodological issues. Most studies report on small self-selected samples recruited from clinics and there is a lack of general population data. Studies also tend to be cross-sectional, which does not allow cause and effect to be established. Future research needs to include longitudinal designs that incorporate qualitative elements to enable a detailed exploration of reasons why people self and misdiagnose FH.

Why Do People Misdiagnose Themselves with Food Hypersensitivity? An Exploration of the Role of Biopsychosocial Factors

Up to 35% of people self-diagnose food allergy or intolerance (food hypersensitivity [FH]), or diagnose it in their child, and self-manage the condition rather than seek a clinical diagnosis. This is much higher than the latest FH prevalence rate, estimated to affect 2–5% of the general population. The actual prevalence rate may be underestimated due to the lack of diagnostic services; however, this can only account for a small proportion of the discrepancy because only a small percentage of self-reported FH can be clinically confirmed. Many people are therefore misdiagnosing their or their child’s symptoms as FH and needlessly removing foods from their or their child’s diet. There are a number of possible reasons for this misdiagnosis, which can be considered from a biopsychosocial perspective. Psychological factors include a confusion over the diagnosis, coincidental pairing of food and symptom, psychological or psychosomatic reactions, and taste aversions. There are also biological mechanisms that have not been fully considered in food allergy research that may be relevant, such as conditioning of the immune system or stress responses. A social context pertains to a greater awareness of FH due to media coverage and changes in food labelling laws. Any of these theories are plausible, but the research to date has a number of methodological issues. Most studies report on small self-selected samples recruited from clinics and there is a lack of general population data. Studies also tend to be cross-sectional, which does not allow cause and effect to be established. Future research needs to include longitudinal designs that incorporate qualitative elements to enable a detailed exploration of reasons why people self and misdiagnose FH.

Parasitic diseases of the respiratory tract

PURPOSE OF REVIEW

The human pulmonary system can be affected by a variety of parasites. This review focuses on the most common parasitic infestations involving the lung, except for protozoon disease.

RECENT FINDINGS

In many parasitic lung conditions, the clinical manifestations and the imaging findings are non-specific and can make diagnosis challenging. Hydatid disease and paragonimiasis involve the lung directly. Chronic schistosomiasis can lead to pulmonary hypertension. Strongyloides stercoralis infestation is capable of transforming into a fulminant fatal disease. In many types of nematode infestations, the pulmonary phase can cause acute eosinophilic pneumonia. Chest radiographs of patients with paragonimiasis and dirofilariasis can cause diagnostic confusion. Cases of tropical pulmonary eosinophilia typically present with refractory bronchial asthma. Most of these diseases are initially diagnosed by detecting eggs or larvae in stool, sputum, pleural fluid or tissue, and are confirmed by serologic testing. Cystic hydatid disease generally requires surgical treatment, whereas almost all other parasitic lung conditions can be treated medically.

SUMMARY

Although most parasites that affect the lung are endemic to tropical and subtropical regions, immigration and travel practices have resulted in transfer of these diseases to other areas. It is important for physicians to know the epidemiologic characteristics, clinical presentations, and treatments of choice for these conditions.