Cyclospora cayetanensis causing diarrhoea in adults in Norfolk, England: report of two cases and review of literature


N Sajjad Raja*, S Schelenz
Dept of Microbiology, Norfolk and Norwich Hospital NHS Trust, Bowthorpe Road, Norwich NR2 3TX, United Kingdom
*To whom corresponding should be addressed;
Dr Nadeem Sajjad Raja
Phone: 00441603611816
Fax: 00441603620190
Email: rajanadeem@doctors.net.uk
Acknowledgement
The authors thank Katy Woodward and the Microbiology technical staff at Norwich Hospital and the Hospital for Tropical Diseases for help with identification of the parasite.

Abstract
Cyclospora cayetanensis is an important emerging infectious disease agent found worldwide causing cyclosporiasis; a condition presenting with prolonged and profuse diarrhoea in immunocompetent and immunocompromised (such as AIDS) patients. It is endemic in some tropical regions of the world and mostly associated with travel to these areas. The prevalence of Cyclospora cayetanensis in the UK remains very low. Cases of cyclosporiasis are often misdiagnosed or even missed due to the lack of understanding of the epidemiological and laboratory features of this pathogen. In this report a 42 year old male animal farm worker and a 45 year old female patient presented with the signs and symptoms of a gastrointestinal illness over a period of several weeks. Cyclospora cayetanensis oocysts were detected in stool specimens. Oral Trimethoprim-sulfamethaxazole 160/800 mg twice daily for 10 days was administered in first patient while second patient improved without specific treatment. This is a first example of a possible link between animals to human spread of Cyclospora cayetanensis in one of the cases. The authors also review the previously reported cyclosporiasis cases in the literature.
Keywords: Cyclospora cayetanensis, cyclosporiasis, protozoa, UK

Introduction
Cyclospora cayetanensis, a coccidian protozoon, has recently emerged as an important cause of gastrointestinal illness in sporadic cases as well as epidemic outbreaks worldwide (1,2). This intestinal parasite causes cyclosporiasis which is characterised by prolonged and relapsing watery diarrhoea, fatigue, abdominal cramps, weight loss and anorexia in immunocompetent as well as immunocompromised patients such as those suffering from acquired immunodeficiency syndrome (AIDS). The exact route of transmission remains unclear but human to human spread is unlikely as oocysts are excreted unsporulated in fresh stool and require time to sporulate in a suitable environment to cause infection. Sources other than human to human transmission should be considered as source of cyclosporiasis (3). The diagnosis of the cyclosporiasis is usually based on the watery diarrhoea and the detection of the oocysts in the stool. On the other hand, several studies have reported the detection of the oocysts from asymptomatic healthy individuals (1,4). It is thought that Cyclospora cayetanensis may be misidentified as Cryprosporidium parvum, especially in immunocompromised patients as there is a strong similarity between the two parasites in modified Kinyoun acid fast stain. It is therefore important for clinical microbiology laboratories to focus on the detection of Cyclospora cayetanensis and to be able to distinguish between these two parasites (1). The prevalence of the Cyclospora cayetanensis remains higher in the developing countries than in the UK, US and Europe. A few sporadic cases associated with overseas travel have been reported in England and Wales in the past (5,6). Here we report two cases of cyclosporaisis in two adults who acquired the infection in the UK.

Case report 1
A 42 years old male developed signs of acute gastrointestinal illness on 3rd October, 2008. His symptoms included watery diarrhoea, fever, fatigue, arthralgia, loss of appetite and weight loss. He visited his general practitioner (GP) after one week of the onset of gastroenteritis. He is currently employed as a pig farm worker in the outskirts of the Norwich. In mid September 2008 all pigs developed dysentery and were managed by veterinary personnel. Despite the management of diarrhoeal illness, the animals did not show any signs of improvement and were later culled. The animal farm was decontaminated with an iodine based disinfectant (Virudine, Antec International, UK). This patient developed gastrointestinal illness after approximately two weeks of the onset of the pigs illness. The patient did not have any travel history and all house hold member were free from such kind of symptoms. The patient was initially managed conservaatively by the GP without antibiotics. A stool specimen was obtained for microscopy and culture and Cyclospora cayetanensis oocysts were seen. Results of blood tests including full blood count, biochemical profile and liver function tests were normal. The patient had no risk factors suggesting an immunodeficiency; however the immunodefiency status was not determined. Standard therapy with oral Trimethoprim-sulfamethaxazole (160/800mg twice daily for 10 days) was subsequently prescribed. Surveillance stool specimen was requested after one week of the treatment which was negative for Cyclospora cayetanensis oocyst and the patient made a full recovery.

Case report 2
A 45 year old female patient who lives in the outskirts of Norwich visited the GP practice on 24th June 2008. Her main complaints were watery and profuse diarrhoea, abdominal pain and myalgia for the last three weeks. There was no contact with other cases of gastrointestinal illness no overseas travel or animal contact during the last one year. Blood tests such as full blood count, liver function tests and renal function tests were within normal range. There were no obvious risk factors to suspect immunodeficiency although an immunodefiency status was not determined. A stool specimen was sent to the microbiology laboratory for microscopy and showed Cyclospora cayetanensis oocysts. She was managed conservatively by the GP. The reference laboratory Hospital for Tropical Diseases, London confirmed the diagnosis. Her diarrhoea improved without any antibiotic. She made full recovery.
Microbiological methods

Stool specimens were sent to the medical microbiology laboratory, Norfolk and Norwich University Hospital, Norwich, UK from the two patients for investigation of gastroenteritis.
Stool specimens were examined microscopically by a concentration technique (formal-ethyl acetate sedimentation and saline lugol technique). This examination detected Cyclospora cayetanensis oocyst in both patient’s stool specimens. The stool specimens were sent away to the reference laboratory (Hospital for Tropical Diseases, London) for confirmation of Cyclospora cayetanensis oocysts. Routine bacteriological cultures of the stool specimens for Salmonella spp, Camplyobacter spp, Shigella spp, Vibrio spp, Yersinia enteroolitica and E. coli O157:H7 were negative.

Discussion
In recent years, reports on sporadic cases and outbreaks of Cyclospora cayetanensis infections have been increased worldwide since it was first linked with gastrointestinal illness in humans in 1977 (4). The prevalence of this organism appears to be low in the developed countries as compared to the tropics and subtropics. In the UK, the reported cases are usually associated with foreign travel (5,6). A small number of infections in patients without a travel history have previously been reported from the United Kingdom (2). Water and fruits such as raspberries are considered as a major route of transmission of this microorganism (6). In 1990, the epidemiological studies of outbreak in Chicago hospital in the US suggested that the water from a tank was responsible for the gastrointestinal illness in the resident doctors who consumed this water (7). Other foods such as mesculun and basil have been linked with the outbreaks in North America. These foods are consumed uncooked and effective washing is not done due to the fear of the damage of leaves. In one study, Cyclospora cayetanensis oocysts were found on the surface of the vegetable after washing (8). A previous study reported a waterborne outbreak of cyclosporiasis from Western Turkey. Water supply to the village was the suspected source of the outbreak which was contaminated with animal excreta during rain fall. Of the total 22 patients, seven had possible stool for Cyclospora cayetanensis and all patients consumed water from same water tank (9). The lengthy sporulation time in the favourable environment further supports the hypothesis that Cyclospora cayetanensis can be transmitted from water and food contaminated with faeces from an infected person (10). The other possible vector for transmission such as animal has not yet been established. In the first case report, the close association of symptomatic pigs with the patient raises the possibility that Cyclospora cayetanensis may be acquired from these animals. Unfortunately we could not obtain animal faeces from the animals for further studies to establish the possible link of animal to human transmission, as all animals were culled two weeks prior the onset of the diarrhoea in this patient. It might be of value to stool specimens from the pigs with gastrointestinal for the presence of Cyclospora cayetanensis oocysts. Treatment may need to be initiated if the oocyst are seen in order to prevent the further spread of this disease. Our second case did not have any obvious identifiable links or risk factors.


Cyclospora cayetanensis affects all ages of both males and females. Clinical features of the cyclosporisis include nausea, prolonged and relapsing watery diarrhoea, vomiting, weight loss, fatigue, loss of appetite, abdominal cramps, fever, chills, arthralgia/myalgia and headache. The symptoms of infection may persist from 4 to 107 days (11,12). In our patients, the symptoms were consistent with previously described symptoms and the duration of illness was approximately two weeks. Prolonged infection due to this protozoan particularly in immunocompromised patients has previously been associated with extra-intestinal symtoms such as cardiac arrest (2), Reiter syndrome (13), Guillian-Barre syndrome (14), biliray disease (15) and acalculous cholecystitis (16).
The identification of Cyclospora cayetanensis oocysts in stool requires well trained laboratory staff. A wet mount examination technique is less sensitive than modified acid fast staining or Kinyoun methods. A previous study suggested the use of modified safranin method for the uniform staining of Cyclospora cayetanensis oocyst (17). Molecular methods such as polymerase chain reaction are also employed for the diagnosis of Cyclospora cayetanensis in patient’s stool. Both cases could have been misdiagnosed or missed as the patient did not travel overseas. The laboratory confirmation was made by a biomedical scientist with an expertise in parasitology. The potential link with pigs should be noted although it has not been confirmed and may have been accidental.


Several antimicrobial therapies such as Trimethoprim-sulfamethoxazole and ciprofloxacin are currently administered to treat the cyclosporiasis in patients (12,18). Trimethprim-Sulfamethoxazole remains the drug of choice in this infection. The standard regimen include; 160/800 mg twice daily orally for 7 days in immunocompetent patients and 160/800 mg four times daily orally for 10 days in immunocompromised patients. Trimethoprim alone or ciprofloxacin can alternatively be used in patients allergic to sulfonamide drugs (18,19). In a randomised control trial study in AIDS patients in Haiti showed the effective management of cyclospriasis by either Trimethoprim-sulfamethoxazole or ciprofloxacin (18). Improvement of diarrhoea and negative stool examination results confirmed the efficacy of the management by these two agents (18).


This paper alerts the physicians to consider Cyclospora cayetanensis in the differential diagnosis of diarrhoea in the UK. Epidemiological studies should be done to investigate the possible mode of transmission of this organism from animal to humans.
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Reference:

  1. SancakB, Akyon Y, Erguven S. Cyclospora infection in five immunocompetent patients in a Turkish university hospital. J Med Microbiol 2006; 55: 459-62.
  2. Burrell C, Reddy S, Haywood G, Cunningham. Cardiac arrest associated with febrile illness due to U.K. acquired Cyclospora cayetanensis. J Infect 2007; 54: e13-5.
  3. ChalmersRM, Nichols G, Rooney R. Foodborne outbreaks of cyclosporiasis arisen in North America. Is United Kingdom at risk? Commun Dis Public Health 2000; 3: 50-5.
  4. Alakpa G, Clarke S, Fagenro-Beyioku A. Cyclospora cayetanensis in Lagos, Nigeria. Clin Microbiol Infect 2003; 9: 731-3.
  5. Green ST, McKendrick MW, Mohsen AH, Schmid ML, Prakasam FR. Two simultaneous cases of Cyclospora cayatensis enteritis returning from Dominican Republic. J Travel Med 2000; 7: 41-2.
  6. Cann KJ, Chalmers R, Nichols G, O’Brien SJ. Cyclospora infections in England and Wales: 1993 to 1998. Commun Dis Public Health 2000; 3: 46-9.
  7. Marshall MM, Naumovitz D, Ortega Y, Sterling CR. Waterborne protozoan pathogens. Clin Microbiol Rev 1997; 10: 67-95.
  8. Ortega YR, Roxas CR, Gilman RH, Miller NJ, Cabera L, Taquiri C, Sterling CR. Isolation of Cryptosporidium parvum and Cyclospora cayetanensis from vegetables collected in markets of an endemic region in Peru. Am J Trop Med Hyg 1997; 57: 683-6.
  9. Aksoy U, Akisu C, Sahin S, Usluca S, Yalsin G, Kuralay F, Oral AM. First reported outbreak of cryptosporidiosis with Cyclospora co-infection in Turkey. Euro surveill 2007; 12: 3142.
  10. Koru O,Araz E, Inci A, Tanyuksel M. Co-infection of Giardia intestinalis and Cyclopsora cayetanensis in an immunocompetent patient with prolonged diarrhoea: case report. J Microbiol 2006; 44: 360-62.
  11. Kansouzidou A, Charitidou C, Varnis T. Cyclospora cayetanensis in a patient with traveller’s diarrhoea: case report and review. J Travel Med 2004; 11: 61-3.
  12. Karanji RM, Gatei W, Wamae N. Cyclosporiasis: an emerging public health conern around the world and in Africa. African Health Sceineces 2007; 7: 62-7.
  13. Connor B, Johnson E, Soave R. Reiter syndrome following protracted symptoms of Cyclospora infection. Emerging Infect Dis 2001; 7: 453-4.
  14. Richardson RF, remler BF, Katirji B, Murad MH. Guillian-Barre syndrom after Cyclospora infection. Musle Nerve 1998; 669-671.
  15. Sifuentes-Osornio J, Porras-Cortes G, Bendall RP, Morales-Villarr F, Reyes-Teran G, Ruiz-Palacios GM. Cyclospora cayetanensis infection in patients with and without AIDS: biliary disease as another clinical manifestation. Clin Infect dis 1995; 29: 613-6.
  16. Zar FA, El-Bayoumi E, Yungbluth MM. Histological proof of acalculous cholecystitis due to Cyclospora cayetanensis. Clin Infect dis 2001; 33: e140-1.
  17. Visvesvara GS, Moura H, Kovacs-Nace E, Wallace S, Eberhard ML. Uniform staining of Cyclospora oocysts in fecal smear by a modified safranin technique with microwave heating. J Clin Microbiol 1997; 35: 730-3.
  18. Verdier RI, Fitzgerald DW, Johnson WD Jr, Pape JW. Trimethoprim-Sulfamethoxazole compared with ciprofloxacin or treatment and prophylaxis of Isospora belli and Cyclospora cayetanensis infection in HIV-infected patients. A randomised controlled trial. Ann Intern Med 2000; 132: 885-8.
  19. Shlim DR, Pandey P, Rabold JG, Walch A, Rajah R. an open trial of trimethoprim alone against Cyclospora infections. J Travel Med 1997; 4: 44-5.