Allergy due to head lice (Pediculus humanus capitis)

A Rare Case of Anemia Secondary to Lice Infestation

Lice are parasitic infections that can infect humans and survive by consuming host blood. They are most commonly associated with a lack of hygiene and occur most commonly in school-age children, homeless populations, and densely populated areas. Lice infections can potentially lead to vector-containing illness and are rarely complicated by acute blood loss anemia. These side effects, while exceedingly rare, are often very significant and potentially life-threatening. Here we present a rare case of severe anemia found in a patient with chronic lice colonization. We hope our findings will broaden the differential for acute anemias and raise awareness of lice infection as a possible cause of acute anemia.

Impact of a health educational interventional program on reducing the head lice infestation among pupils in an elementary school of a sub-tropical region: a quasi-experimental study

BACKGROUND

Pediculosis is an important social challenge that can be caused by human head louse, Pediculus humanus capitis. This infestation is cosmopolitan, especially in countries with low hygiene and sanitation. Regular health education classes for students and their parents are required to reduce this infestation in schools and families. This study aimed to evaluate the impact of a health education intervention program on reducing head lice among pupils of an elementary school.

METHODS

In a quasi-experimental study, a total of 880 elementary school girls were screened for pediculosis in (2017-2018). The prevalence of pediculosis follow-up continued monthly until the end of the school year after a two months educational intervention course. Visual inspection was applied for initial diagnosis of infection. The suspected cases were confirmed by wood lamp and potassium hydroxide (KOH) microscopic examination. Also eight questions about diagnostic, epidemiology, treatment and prevention were answered in a questionnaire by 50 volunteer parents before and after the training intervention course, to evaluate their general knowledge and measure the effectiveness of learning. All data were statistically analyzed using SPSS software (version 20.0, SPSS, Inc., Chicago, IL, USA). McNemar's test was also applied to investigate the prevalence rate before and after the intervention. A p -value of less than 0.05 was considered as statistically significant.

RESULTS

At the beginning of study, pre-intervention prevalence of pediculosis among pupils was 8.4% (49/594). The mean age in all pupils was 9.86 ± 1.83 years old and the most infestation was shown in fourth-grade students with 10 years old. Analysis of statistics demonstrated a significant difference between having infestation and the number of members in the families. Post-intervention phase led to a decreased prevalence of pediculosis in pupils to 3% (8/594) (p-value < 0.05). Based on statistical analysis of questions before and after the training in the questionnaire, a significant increase of parental knowledge was observed on the prevention program of pediculosis (p-value < 0.001).

CONCLUSION

The prevalence of pediculosis was significantly reduced following the educational interventions in the school. The applied interventions may be implemented in other residual centers to get rid of this important infestation.

Prevalence of Pediculus capitis in schoolchildren in Battambang, Cambodia

BACKGROUND/PURPOSE

Pediculus capitis is the most common human ectoparasite. When it feeds on the blood through the scalp of its host, the anticoagulant in its saliva causes scalp inflammation and itching, and consequent scratching by the host causes further inflammation from bacterial infection. P. capitis infestation is currently a common parasitic dermatosis and a critical public health concern in underdeveloped countries.

METHODS

Through naked eye inspection of P. capitis on or in the hair from 323 school children in Cambodia.

RESULTS

A total of 143 children (44.3%) were found to have P. capitis infestation. Univariate analysis revealed that girls had a significantly higher infection rate than boys. Overall, young aged schoolchildren (10 yrs old ≤) showed significantly higher infection rate than old aged schoolchildren (>10 yrs old). Groups stratified by time revealed that schoolchildren studied at the afternoon classes than morning classes in Tuol Prum Muoy Primary School had a significantly higher risk in acquisition of P. capitis infestation. Multivariate analysis results indicated that relative to the boys, the girls were at a significantly higher risk of contracting P. capitis infection. When stratified by inspection time with the Tuol Prum Muoy Primary School morning classes as the reference, the Tuol Prum Muoy Primary School afternoon classes exhibited a significantly higher risk of P. capitis infection.

CONCLUSION

Primary school children in Cambodia have a high P. capitis infection rate and thus require effective treatment and prevention measures to treat symptoms and lower the infection rate.

Lice induced immuno-oxidative wreckage of goats

The present study aimed to evaluate the immuno-oxidative patho-biology of lice infestation in goats. Sixty goats were divided into five groups; sucking lice (Linognathus africanus) infested (Group 1, n=12), chewing lice (Bovicola caprae) infested-mild (Group 2, n=12), chewing lice (B. caprae) infested-moderate (Group 3, n=12), chewing lice (B. caprae) infested-severe (Group 4, n=12) and healthy control (Group 5, n=12). To assess the pathological changes, markers of oxidative stress (lipid peroxidation-LPO, reduced glutathione-GSH, superoxide dismutase-SOD, Catalase-CAT and total antioxidant capacity-TAC), the markers of immune status (Tumour necrosis factor alpha- TNF-α, Interleukin-10- IL-10, Transforming growth factor beta 1- TGF-β1, ratios of TNF-α/IL-10 and TNF-α/TGF-β1) and hemato-biochemical status were evaluated. Significant anemia, hypoglycemia, hypoproteinemia and hypoalbuminemia were observed in caprine pediculosis irrespective of the type of lice infested. Remarkably increased oxidative stress was observed in chewing lice infested goats and no significant changes in oxidative stress markers were observed in sucking lice infested goats. TGF-β mediated suppression of Th1 and Th2 immune responses was observed in sucking lice infested goats; whereas, a Th2 cytokine dominant inflammatory response was observed in chewing lice infested goats. From the present study, it may be concluded that sucking lice infestation produces remarkable immunosuppression and chewing lice infestation produces significant oxidative stress and inflammatory responses in goats.

Mites and other indoor allergens - from exposure to sensitization and treatment

House dust mites, cats and dogs are amongst the most frequent sources of indoor allergens in Europe. The fact that the allergens of house dust mites cause allergic disease through inhalation of house dust was discovered in 1964. The diagnosis of mite allergy is regularly complicated by its often nonspecific symptoms, which frequently develop insidiously and by no means always include attacks of paroxysmal sneezing and itching. Antibody-based immunological detection methods can be used to measure exposure to mite allergens. The structure and function of more than 20 allergens from Dermatophagoides pteronyssinus and D. farina are known. Other relevant indoor allergens come from mammals kept in households. Here again, allergens have been described and diagnostic as well as exposure-measurement tools are available. It is important to remember indoor pests and other „unwelcome lodgers“ as a possible cause in the case of unexplained symptoms experienced indoors. This short overview summarizes the current key points on the subject of „mites and other indoor allergens“. The present article provides an overview of several articles published in a special issue of the German journal Allergologie [February 2015; 38(2)] on the subject of „Mites and other indoor allergens“.

[Cockroaches and co. The role of health pests as allergen source]

In most of the cases health pests are carriers of pathogens or parasites which have a negative impact on human health or affect the health of other mammals. What is lesser known is that they can also act as allergens. Most of the health pests in this sense belong to the arthropods, such as cockroaches (Blattaria), mosquitos (Culiciformia), lice (Pediculus humanus corporis), fleas (Siphonaptera) and ticks (Argasidae). In the group of vertebrates rats (Rattus norvegicus and Rattus rattus), house mice (Mus musculus) and pigeons (Columba livia domestica) are also classified as health pests. Also storage pests which are not carriers of pathogens can induce secondary infestation with hygiene pests or molds and have an underestimated impact on human health. In this article selected examples of health pests and also storage pests as an allergen source are described, taking into account the sensitization prevalence and identified single allergens.

Insect stings: clinical features and management

BACKGROUND

In human beings, local and systemic reactions can be caused both by blood-sucking insects and by venomous insect stings. In Central Europe, the insects that most commonly cause such reactions are honeybees, certain social wasps, mosquitoes, and flies.

METHODS

This article is based on a selective literature review, including guidelines from Germany and abroad.

RESULTS

Insect venom induces a toxic reaction at the site of the sting. Large local reactions are due to allergy and occur in up to 25% of the population; as many as 3.5% develop IgE-mediated, potentially life-threatening anaphylaxis, of which about 20 people die in Germany each year. Mastocytosis is found in 3% to 5% of patients with sting anaphylaxis, rendering these patients prone to very severe reactions. Blood-sucking by hematophagous insects can elicit a local allergic reaction, presenting as a wheal or papule, in at least 75% of the population. Large local reactions may ensue, but other diseases are rare. The acute symptoms of an insect sting are treated symptomatically. Patients who have had a systemic reaction or a large local reaction due to insect allergy must take permanent measures to avoid further allergen contact, and to make sure they can treat themselves adequately if stung again. Most patients with systemic anaphylactic reactions to bee or wasp stings need specific immunotherapy.

CONCLUSION

Insect stings can cause severe disease. Anaphylaxis due to bee or wasp stings is not a rare event; specific immunotherapy protects susceptible persons from further, potentially life-threatening reactions.