Blastocystis, urticaria, and skin disorders: review of the current evidences

Blastocystis is one of the most common intestinal protozoan parasites worldwide, which is linked to cutaneous lesions and urticaria. In a setting of systematic review, the data on the association of Blastocystis infection with cutaneous lesions were searched in order to summarize the main clinical symptoms, diagnostic methods, treatment, and outcome of the patients. The search identified 28 eligible articles, including 12 cross-sectional studies and 16 case reports/case series (including 23 cases). A diverse spectrum of skin symptoms, mainly urticaria, rash, and itching, was reported from the studies. Of the 23 infected cases with the skin symptoms, gastrointestinal symptoms were reported from the 16 cases, whereas 7 cases with urticaria had asymptomatic infection. The most frequent subtypes were ST1, ST2, and ST3, respectively. Metronidazole, paromomycin, and tinidazole were the most prescribed drugs in patients with single Blastocystis infection. Notably, urticaria and other cutaneous symptoms of all treated patients were resolved after treatment. In conclusion, this study indicates that Blastocystis infection can be a neglected cause of urticaria and skin disorders. Since the treatment of Blastocystis infection is simple, screening and treatment of this infection should be considered in patients with urticaria and other skin disorders.

Traumatic rupture of a hydatid cyst of the liver presenting with skin lesions

The hydatid cyst is the evolution of a parasitic infection caused by Echinococcus granulosus and is an endemic disease in Turkey. The hydatid cysts of the liver can give origin to several complications and the rupture is one of them. Rupture can occur spontaneously or as a result of external trauma. The presentation with skin lesions is very rare. We present a 20-year-old male patient who presented himself after a car accident, and was diagnosed with a rupture of traumatic hydatid cysts due to hives rash. In the operation, a scolicidal gent was administered to the cyst, the cyst wall was partially excised and the germinative membranes were removed. Medical treatment with albendazole was started. The postoperative period was quiet. The intraperitoneal traumatic rupture of a hydatid cyst is rare, but it can cause severe anaphylactic reactions and biliary peritonitis. Although a rare and broken hydatid cyst due to trauma may present with skin lesions in a patient in an endemic region, it should be considered in the differential diagnosis. KEY WORDS: Primary hydatid cyst, Trauma, Urticaria.

Toxocara Canis and Chronic Urticaria

No Abstract.

Toxocara Canis IgG Seropositivity in Patients with Chronic Urticaria

We aimed to investigate IgG antibody levels specific to Toxocara canis (T. canis), a parasite which subsists in dog's intestine, on serum samples obtained from patients with chronic urticaria (CU) to evaluate effective risk in CU etiopathogenesis. In this study, 73 patients diagnosed with CU and 109 healthy individuals as control group, were included. Various factors such as sex, age, education and income, daily hand washing habits, history of dog owning and soil eating were questioned in patient anamnesis. T. canis IgG antibodies were detected using an enzyme linked immunosorbent assay (ELISA) kit prepared with T. canis larval excretory-secretory antigens. Positive results were confirmed with western blot (WB) WB test. We found T. canis IgG positivity in 17.8% (n=13) of patients (n=73) with CU. But we did not observe any T. canis IgG positivity in healthy controls (n=109). Low molecular weight bands (24-35 kDa) were observed in 11 samples in WB analyses while two of the samples were weakly positive. It is revealed that dog owning history increases T. canis seropositivity 12.9 times while insufficient daily hand washing habit (less than six times a day) increases seropositivity 20.7 times. Our study showed that T. canis may trigger CU since we found 17.8% seropositivity in 73 patients with CU and none in 109 healthy individuals. Moreover, various socio-demographic characteristics have been shown to affect T. canis seropositivity in patients with CU.

Tissue Parasites in Patients with Chronic Urticaria

Chronic urticaria is an important diagnostic and therapeutic problem. We aimed to investigate the sero-prevalence of tissue parasites causing toxocariasis and fasciolosis in patients with chronic urticaria. All cases were analyzed for antibodies against Toxocara canis and Fasciola hepatica by modified (homemade) ELISA. The excretory/secretory products of Toxocara and Fasciola were used as antigens (ES-ELISA) in the test. In this study, the highest toxocariasis seropositivity (29.0%) rate and the highest fasciolosis seropositivity (14.5%) rate were found in patients with chronic urticaria. Fasciolosis seropositivity and total seropositivity of toxocariasis and fasciolosis in patients with chronic urticaria was significantly higher than in healthy controls (p<0.05). Toxocariasis seropositivity in patients with chronic urticaria was not significantly higher than that in healthy controls (p>0.05). We suggest that parasitic infections should be considered as an important cause of chronic urticaria. Serological methods should be used to expose the diagnosis of tissue parasites in such cases.

A rare manifestation of cysticercosis infestation

There are many causes of urticaria, which may vary from infections to malignancy. Among the infections, infestations by cysticercosis (larval stage of the tapeworm called Taenia solium) is an important cause. The present report is of forty four years old female who presented with urticaria and swelling on face. The swelling was later diagnosed as cysticercosis by noninvasive ultrasonography. The urticaria subsided after the treatment of cysticercosis. We report this case for rarity of its presentation.

Different fish-eating habits and cytokine production in chronic urticaria with and without sensitization against the fish-parasite Anisakis simplex

BACKGROUND

Anisakis simplex sensitization has been associated with acute, but also with chronic urticaria. The objective of this study is to characterize chronic urticaria with (CU+) and without sensitization (CU-) against the ubiquitous fish parasite A. simplex in a transversal and longitudinal evaluation.

METHODS

16 CU+ and 22 CU- patients were included and assessed for Urticaria activity score (UAS), fish-eating habits by standardized questionnaire and cytokine production (assessed by flow cytometric bead-based array) of peripheral blood mononuclear cells after stimulation with A. simplex extract or Concanavalin A (Con A). Patients were randomly put on a fish-free diet for three months and UAS, as well as cytokine production were again assessed. A difference of ≥1 in UAS was defined as improvement.

RESULTS

There was no difference in UAS in both groups. Anisakis induced IL-2, IL-4 and IFN-γ production was higher in CU+. Con A induced IL-6 and IL-10 production was higher in CU+. CU+ was associated with higher total fish intake, whereas CU- was associated with oily fish intake. The correlation of UAS was positive with oily fish, but negative with total fish intake. There was a better UAS-based prognosis in CU+ without diet. Improvement was associated with higher Con A induced IL-10/IFN-γ as well as IL-10/IL-6 ratios. Further, previous higher oily fish intake was associated with improvement.

CONCLUSIONS

Our data confirm the different clinical and immunological phenotype of CU+. Our results show a complex relationship between fish-eating habits, cytokine production and prognosis, which could have important consequences in dietary advice in patients with CU. When encountering A. simplex sensitization, patients should not be automatically put on a diet without fish in order to reduce contact with A. simplex products.

Chronic urticaria in a middle-aged woman

We report the case of a 56-year-old female who suffers from chronic urticaria and digestive symptoms, suggesting parasitic infection. Neither repetitive ova and parasite examinations in stools, nor duodenal aspiration examination reveals any parasite. The patient is treated by tinidazole, but the symptoms reappear ten days later. An additive ELISA test on stool remains positive for Giardia Lamblia; the patient receives once more tinidazole and symptoms totally disappear. This case report illustrates that the association between urticaria and digestive symptoms should guide the clinician to the diagnosis of Giardia Lamblia infection, and it shows the importance of a rapid and highly sensitive diagnostic test for giardiasis, like the ELISA test.

[Clinical and epidemiological characteristics of blastocystis hominis]

BACKGROUND

Blastocystis hominis is an intestinal parasite known since long. It is cosmopolitan and lives in the colon. It is still the subject of controversy regarding its pathogenicity and possibly opportunistic character.

AIM

We exhibit in this article the results obtained for 4 years on the epidemiological, clinical and biological character and opportunistic Blastocystis hominis, often overlooked in the examination of parasitological laboratories city.

METHODS

This is a retrospective study of 3257 stool examination (PSE), performed in the Mycology Laboratory of Parasitology of the Charles Nicolle Hospital in Tunis over a period of 4 years (January 2005-December 2008). Detection of Blastocystis hominis has been made by microscopic examination of samples by direct examination and concentration.

RESULTS

Blastocystis was found in 7.27% of cases and 48.5% in men. Endolimax nanus is the parasite most frequently associated with Blastocystis (40.4% of cases). The port was symptomatic in 72.1% of cases, diarrhea is the symptom most often found (27.7%). There is a seasonal distribution; in fact, it is more frequently diagnosed in summer and autumn.

CONCLUSION

The absence of gravity and the saprophytic nature of this infection do not lead to an indication for treatment even among profoundly immunosuppressed individuals. Only the persistence of clinical disorders associated with the detection of the parasite and in the absence of other micro-organisms and intestinal parasites justifies the treatement. Metronidazole is the molecule used conventionally.

[Cutaneous manifestations on toxocariasis cases hospitalized in the Paediatric Diseases Clinic of Iaşi, between 2005-2008]

The authors present the results of retroprospective epidemiological, clinical and laboratory diagnosis on toxocariasis cases hospitalized in the Paediatric Diseases Clinic of Iaşi, between January 2005- June 2008.

MATERIAL AND METHOD

The study included a number of 228 children.

RESULTS

Cutaneous manifestations were present in 65 children: 30 boys (46.15%) and 34 girls (52.30%), with a slight advance of the urban environment (53.84%). The age distribution highlighted a predominance of 1-6 age (66.15%). Cutaneous manifestations were pruritus, urticaria, atopic dermatitis, prurigo. The distribution of toxocariasis in children patients in Moldavia, Romania, highlighted a predominance in Iaşi. The laboratory diagnosis of the children with cutaneous manifestations: hypereosinophilia was present on 87.69% of the children associated with hyperleucocytosis. All the patients were serologicaly confirmed with toxocariasis. The children responded well to treatment with albendazole.

[The role of protozoan parasites in etiology of urticaria]

In order to investigate a possible link between parasites and chronic urticaria, the prevalence of intestinal protozoans in stool samples of individuals with chronic urticaria (n=55) and healthy controls (n=43) were evaluated with native lugol, formol-ethyl acetate concentration and trichrom dye, modified acid fast. In the case of Giardia intestinalis (G. intestinalis) ELISA was also used. In the study 29.1% of the patients were found to have protozoan (Blastocystis hominis + G.intestinalis) infections. On the other hand, only 11.6% of the patients in healthy group were having a protozoon infection, all of which were B. hominis. There was no statistically significant difference between the patient group and control group regarding the frequency of B. hominis presence. Also, the number of G.intestinalis positive patients were also statistically different in patient group from those of healthy controls. In patients whom were positive for protozoan infections, agent specific therapy was used. In 7 of these patients symptoms of the disease were subsided with this therapy while six continued to have relapses. Three patients had missed the control visits therefore the course of the disease was not evaluated. As a conclusion, protozoans should be considered in the etiology of chronic urticaria and stool examination should be done in these patients routinely.

[Diagnostic image (391). A man with fever and urticaria after a trip to Uganda]

A 35-year-old man presented with fever and severe urticaria after visiting Uganda. His symptoms were caused by acute invasive schistosomiasis, also known as Katayama fever.

[Retrospective clinical and laboratory study of the toxocariasis cases hospitalised between 2005 and 2008]

The authors present the results of retroprospective clinical and laboratory diagnosis on toxocariasis cases hospitalized in the Paediatric Diseases Clinic of Iaşi, between January 2005-June 2008.

MATERIAL AND METHOD

The study included a number of 228 children.

RESULTS

The most frequent clinical manifestation was pulmonary symptoms 80.70%: dyspneea, wheesing, asthma, cough, interstitial pneumonitis. The most frequent digestive symptoms were abdominal pain 41.22%, hepatosplenomegaly 29.38%; cutaneous manifestations were pruritus and urticaria. The laboratory diagnosis: hypereosinophilia was present at 94.73% childrens associated with hyperleucocytosis and hyper-gammaglobulinemia. All the patients were serologic confirmed with toxocariasis. The children responded well to treatment with albendazole.

[Parasites as a cause of urticaria. Helminths and protozoa as triggers of hives?]

Urticaria is one of the most prevalent disorders in dermatological practice. The disease can be incapacitating. There are clear pathophysiological and epidemiological hints that helminths and protozoa are rare but treatable causes of acute and chronic urticaria. Doctors and patients are often not aware that parasitic diseases are increasingly common even in industrialized countries due to a steep rise in migration and international travel. This review presents the most important parasitic causes of urticaria and provides relevant details regarding personal history, clinical presentation, diagnosis and therapy.

[New data on anisakiasis]

Acute anisakiasis is generally due to the third-stage larvae of Anisakis simplex, and occasionally to other anisakidae. Human infection occurs through consumption of raw seafish, and especially herring, hake, black plaice and cod. Patients sensitized by prior consumption of parasitized fish develop, within a few hours, violent abdominal pain and an allergic reaction. Anisakis-induced urticaria is seen in about one in five cases. Preventive measures have reduced the number of cases. In France for example, the number of cases fell four-fold between 1977-1991 and 1992-2005. In 1990 Kasuya [1] reported chronic anisakiasis related to consumption of cooked parasitized fish. Seafish-induced urticaria might be an allergic response to Anisakis larval antigens rather than to the fish itself. Indeed, 11 patients with mackerel-related urticaria all had a positive reaction to Anisakis simplex larval antigen, while none reacted to mackerel antigen. A low-molecular-weight thermostable A. simplex allergen causes chronic urticaria, angioedema and even anaphylactoid reactions. Victims have a genetic predisposition (HLA class II alleles) that is uncommon in France and Germany but frequent in Japan. A number of cases have been observed in Spain, where fish is particularly popular. Immunoblotting shows cross-reactions between antigens of A. simplex and Toxocara canis, nematodes belonging to the same superfamily. At present, the only way to avoid contracting anisakiasis is not to eat raw or even cooked parasitized seafish.

Fever and urticaria in an African refugee

An 11-year-old African refugee presented with fever and urticaria commencing 2-h after taking praziquantel. He had been well previously, and the praziquantel was given to treat a serological diagnosis of schistosomiasis. The main differential diagnosis was between acute schistosomiasis and a drug reaction.

Giardia lamblia — Ursache von Urtikaria und Pruritus oder zufällige Assoziation?

Three patients with chronic urticaria or pruritus were found to suffer from an asymptomatic intestinal infection caused by the protozoan Giardia lamblia. Treatment with metronidazole per os or tinidazole per os was successful; the pruritic symptoms in one patient improved markedly.Giardia lamblia (Giardia intestinalis) are enteroparasites and produce gastrointestinal symptoms such as acute and chronic diarrhea. Cutaneous manifestations associated with giardiasis occur extremely rarely. Urticaria and itching may be explained as an infection-associated allergy. Hitherto, the following cutaneous signs have been described: urticaria, angioedema, mouth ulcers, pruritus, atopic dermatitis, and anal eczema.We considered that the cutaneous manifestations described here, i. e., urticaria and itching, were secondary to the associated gastrointestinal infection due to Giardia lamblia cysts and trophozoite forms, as they disappeared under specific treatment with metronidazole or tinidazole.

Toxocara canis and chronic urticaria in Egyptian patients

Toxocariasis is a common parasitic condition present all over the world with high seroprevalence rates even among asymptomatic individuals. Recent diagnostic techniques have revealed a wider scope of clinical syndromes due to toxocariasis including dermatological disorders and particularly urticaria. The patients with chronic urticaria were enrolled for serological toxocariasis investigations. The results pointed to a possible role of T. canis in-ection in chronic urticaria patients, especially those exposed to an increased risk of environmental exposure to toxocariasis.

Anisakis simplex: sensitization and clinical allergy

PURPOSE OF REVIEW

Whereas gastric anisakiasis has been known for several decades, the implications of Anisakis simplex-related allergic disorders had not been thoroughly studied until the late 1990s. This article reviews recent knowledge of allergic disorders ascribed to A. simplex contact or parasitism.

RECENT FINDINGS

Gastroallergic anisakiasis describes an acute hypersensitivity reaction emerging in the context of an acute parasitism by the nematode A. simplex. But other frequent allergic disorders like chronic urticaria are now being studied for a possible relationship with A. simplex parasitism. In recent investigations, non-IgE mediated mechanisms, such as the involvement of other immunoglobulin isotypes (IgG4), or non-immunological events are discussed.

SUMMARY

The experience of the last several years shows that allergic hypersensitivity symptoms in gastroallergic anisakiasis are clinical events accompanying a wide range of immunologic reactions as a host response against a ubiquitous parasite. The discussed and reviewed studies should motivate allergists around the world to search for this entity. Further studies in the field of allergy could benefit from the experience of this peculiar food-related disorder.

Chronic urticaria and blastocystis hominis infection: a case report

We report a case of a 45 year old woman which fulfilled the criteria of chronic urticaria (remitting and relapsing bouts of erythematous and pruriginuos lesions without angioedema, lasted four months). Cutaneous manifestations were not related to a specific inducing factor, had no benefit from antihystamine and steroid drugs and were associated sometimes with mild gastroentric disorders. Patient was submitted to extensive clinical, laboratory and intrumental investigations which permit to exclude many conditions: allergy to inhalants, food, insects and drug adverse reactions, autoimmune urticaria, autoimmune diseases, neoplastic and infectious diseases. Finally coprocolture disclosed the presence of Blastocystis hominis in stool samples thus permitting to associate urticaria to parasitic infection. Both cutaneous manifestations and mild abdomen disturbs disappeared after appropriate treatment. Despite the high diffusion the aetiopathogenesis of chronic urticaria remains often undefined. A large number of parasites have been correlated with urticaria but few data exist as regards Blastocystis hominis infection; then our findings may add evidence to the role of this parasite in inducing chronic urticaria. Considering that Blastocystis hominis is a modest pathogen for humans, the mechanism is probably the typical one of cutaneous allergic hypersensitivity; antigen parasites induce the activation of specific clones of Th2 lymphocytes, the release of related cytokines and the consequent IgE production.

Is Anisakis simplex responsible for chronic urticaria?

The association of chronic urticaria (CU) to parasitic infestations has been poorly studied. Recently, sensitization to the parasite larva Anisakis simplex has been described as the cause of acute urticaria and anaphylaxis. The aim of this work was to study the relationship between sensitization to A. simplex and CU. One hundred one patients with CU were studied. Data of possible contacts with A. simplex were collected and the usual CU study was performed. Furthermore, total and specific immunoglobulin E (IgE; Pharmacia CAP system IGE fluorescence enzyme immunoassay: CAP) to A. simplex, Ascaris lumbricoides, Echinococcus granulosus, and Toxocara canis were determined as well as skin-prick test with A. simplex and serology to E. granulosus. In accordance with the results of the CAP to A. simplex, the patients were divided into two groups, positive and negative, and, subsequently, subdivided into two other subgroups that were alternatively told to stop eating fish or seafood in their diet or to continue with their normal diet. Checkups were performed at 6, 12, and 18 months. Thirty-five percent of the patients had positive skin tests to A. simplex, and CAP to A. simplex was positive in 55%. The fish-eating habits, acute or chronic gastrointestinal disease, and the background of abdominal surgery were not related to the results of the CAP and/or skin test to A. simplex. A total of 21.8% of all the patients had detectable CAP to A. lumbricoides, 91% of whom had positive CAP to A. simplex. Three patients had specific IgE to T. canis and five patients had specific IgE to E. granulosus, in the absence of positive serology. All had specific IgE to A. simplex. Present infestation could not be proved in any of them. The clinical evolution and variations of CAP to A. simplex and of total IgE were not statistically different among the groups during the 6, 12, and 18 months of the study. The percentage of sensitization to A. simplex in patients with CU is elevated and determines the sensitization to other parasites because of cross-reactivity. We have not found any causal relationship between the presence of specific IgE to A. simplex and CU. The clinical importance of this finding in this disease is still undetermined.

Acute generalized exanthematous pustulosis in cystic echinococcosis: immunological characterization

We report the first case, to the best of our knowledge, of a woman suffering from cystic echinococcosis of the liver, who consequently developed urticaria and acute generalized exanthematous pustolosis (AGEP). Serum immunoglobulin (Ig)E and IgG4 specific to Echinococcus granulosus antigens were detected by immunoblotting. Furthermore, the intracellular cytokine analysis revealed a prevalent T-helper 2 polarization. It can be reasoned that, while the presence of IgE specific to various E. granulosus allergens may be responsible for the chronic urticarial manifestations, the detection of IgG4 specific for E. granulosus antigens, forming immunocomplexes, may be related to the development of the AGEP.

[Human blastocystosis: prospective study symptomatology and associated epidemiological factors]

An attempt has been made to contribute to the understanding of the symptoms and factors associated with the Blastocystis Hominis infection, as seen in persons seeking outside consultation from the Dermatological and Transmissible Diseases Department (DTDD) at the C.H.N.H. This is a case-control study carried out in people between the ages of 5 and 80 in a period from January to March 1999. The cases tested positive in parasitological tests for Blastocystis Hominis and were absent of other enteropathogens. The controls tested negative in parasitological tests for Blastocystis Hominis and were absent of other enteropatoghens. A clinical chart was used to register details of symptomatology and factors associated with the Blastocystis Hominis infection. 74 cases and 70 controls were studied, matched by sex and age. A statistical correlation was obtained (p<0.05) among symptomatic persons and presence of Blastocystis Hominis (91,9%). The symptomatology associated with the Blastocystis Hominis infection by order of statistical significance (p<0.05) was: Abdominal pain (OR=3) 1.47<OR<6.60, abdominal ballooning (OR=2.36) 1.06<OR<5.29, urticaria (OR=3.19) 0.81<OR<12.48. The only risk factor associated with the Blastocystis Hominis infection was the consumption of unboiled water (OR=2.52) 1.01<OR<5.83. In conclusion, Blastocystis Hominis is associated to symptomatic subjects with abdominal pain and ballooning and urticaria, who possess at least two or three positive tests. This infection would be facilitated by the consumption of unboiled water.

[Acute schistosomiasis: fever and eosinophilia, with or without urticaria, after a trip to Africa]

Despite treatment for malaria two travellers who acquired fever in Africa continued to have complaints: a 25-year-old Dutch woman and a 25-year-old Australian man. On questioning they appeared to have swum in Lake Malawi and a diagnosis of acute schistosomiasis was made, confirmed by serological tests. This syndrome, also called Katayama fever, is characterized by fever, oedema, urticaria and eosinophilia. The aetiology is not fully elucidated but it is supposed to be caused by immune complexes initiated by maturing worms and eggs. Patients who acquired fever in an endemic area must be questioned about contact with fresh water. Serological tests are important for the diagnosis. Treatment is with praziquantel but it is advised to treat only after the acute phase. During the acute manifestations corticosteroids may be necessary. Prevention is by avoiding contact with infected water. There is no vaccine. The role of artemisinin drugs in prevention is currently being studied.

Anisakis and fish induced urticaria

Skin tests using prepared Anisakis antigen and commercially available fish antigen were done. Also, specific IgE detection for Anisakis was done by RAST method. Two patients out of 20 showed positive skin test and positive RAST to larval Anisakis antigen, and negative skin test to fish antigen. These 2 patients were considered hypersensitive to Anisakis.

[Allergy to Anisakis simplex. Report of 2 cases and review of the literature]

Anisakis simplex is a nematode which parasitizes mainly fish and cephalopods and accidentally human beings after ingestion. Apart from the different digestive syndromes, this organism has recently been involved as cause of IgE-mediated allergic reactions of variable degree (urticaria to severe angioedema). In this report three patients with the diagnosis of allergy to Anisakis simplex are reported and a review of the literature is made.

Rheumatic manifestations in the course of anaphylaxis caused by Anisakis simplex

Human anisakidosis is a parasitic infection caused by the larvae of Anisakis simplex. Classical clinical manifestations include epigastric pain, occlusion, diffuse abdominal pain, appendicitis, and anaphylactoid reactions. Arthralgias or arthritis have been infrequently reported. We present three patients with proven hypersensitivity to A. simplex together with rheumatologic complaints after ingestion of parasitized fishes. A. simplex must be considered in the differential diagnosis of arthralgias/ arthritis especially if associated with urticaria.

Respiratory symptoms and subcutaneous granuloma caused by mesocercariae: a case report

A 38-year-old man with no history of pulmonary disease developed intermittent hives and bronchospasms shortly after returning from a hunting trip. Approximately one year later, examination of an excised subcutaneous nodule demonstrated infection with a mesocercaria (larval trematode). The morphology of the parasite was consistent with infection with a parasite of the Alaria spp. or Strigea spp. Eating undercooked wild goose meat during the hunting trip was the most likely source of infection. This appears to be the first report of human infection with mesocercariae acquired through the ingestion of wild goose meat.

[Back again: the clothes louse (Pediculus humanus var. corporis)]

In two homeless men aged 38 and 32 years, who suffered from itching, infestation with body lice (Pediculus humanus var. corporis, a.k.a. clothes lice) was diagnosed. This infestation is rare in the Netherlands. In 1993 and 1994 and infection with body lice was registered 41 times in 31 patients at the clinic for homeless of the Community Health Service of Utrecht. The body louse can be seen by the naked eye. Treatment is by hygienic measures, pediculicides if necessary, and by prevention. Important to recognize is that P. humanus can be the vector of trench fever (Bartonella quintana), relapsing fever and typhus.

Zoonoses of dermatological interest

The zoonoses are those diseases transmitted from animals to humans. Although commonly thought to be infectious in origin such as scabies or dermatophytosis, inflammatory processes may also be zoonotic. Contact dermatitis may result from allergens being carried from animals to humans. Although the scabies mite is somewhat species specific, various mites sometimes have the opportunity of producing skin disease on man (ie, canine scabies, porcine scabies, and feline scabies [notoedric mange]); cheyletiellosis is caused by a similar mite, often found in rabbits. The index case of superficial fungal infections may be the household pet, whereas the cause of flea bite dermatitis (papular urticaria) may be the lack of an animal, resulting in the flea choosing a human for feeding. Understanding zoonotic skin diseases will improve the clinician's diagnostic skills. Both the human and animal patient will then receive more effective treatment in a quicker fashion.

Papular urticaria

The diagnosis of papular urticaria has evolved over the years and has many synonyms. Its most common present day usage relates to a cutaneous reaction presumably from an apparent exposure to insects. The evolving science in this area is allowing a better understanding of potential sources including newer tools to look at antigens from insect proteins injected after bites from flying insects and some other environmental arthropods. Insight to etiology is important and can be partially determined by clinical history and clinical pattern of symptoms. The usual approach in practice is to treat symptomatically first while investigating etiologies. Increasing appreciation of the role of environmental mites and ectoparasites has allowed us more precision in diagnosis to specifically treat the cause. The primary challenge in therapy often relates to the achievement of the goal of symptom relief. This is often difficult because of the chronicity of the syndrome when the patient is seen by a specialist. Both the search for etiology and symptomatic relief often need to be aggressive to achieve the desired therapeutic benefit for the patient.

Urticaria and giardiasis

This study was carried out on 50 patients affected with urticaria: <i>Giardia lamblia</i> was isolated in 6 patients (12%). The relationship between intestinal giardiasis and urticaria is discussed.