Cutaneous myiasis due to Dermatobia hominis : A case report from eastern Sudan

Cutaneous myiasis (CM) is invasion of human skin by larvae of dipterous flies. CM is encountered world-wide and is endemic in several tropical countries, mainly in central and south American. Cases have been reported in non-tropical countries such as USA, UK, Germany, and Japan 3,4,5. . Patients with CM due to Dermatobia hominis usually suffer from painful pruritic furuncular skin lesion with a serous or seropurulent discharge accompanied by a crawling sensation. The disease may resolve spontaneously, however conservative and/or surgical treatment may be indicated. Fatal CM due to D. hominis was reported from Brazil where a scalp lesion had disseminated into the brain. In Sudan, CM seems uncommon, unreported or probably underdiagnosed. In this communication we describe a case of CM due to D. hominis which seems to have been acquired from an indigenous source.

Cutaneous myiasis due to Dermatobia hominis: a case report from eastern Sudan. Cutaneous myiasis (CM) is invasion of human skin by larvae of dipterous flies 1 . CM is encountered world-wide and is endemic in several tropical countries, mainly in central and south American 2 .
Cases have been reported in non-tropical countries such as USA, UK, Germany, and Japan 3,4,5. . Patients with CM due to Dermatobia hominis usually suffer from painful pruritic furuncular skin lesion with a serous or seropurulent discharge accompanied by a crawling sensation.
The disease may resolve spontaneously, however conservative and/or surgical treatment may be indicated. Fatal CM due to D. hominis was reported from Brazil where a scalp lesion had disseminated into the brain 6 . In Sudan, CM seems uncommon, unreported or probably underdiagnosed. In this communication we describe a case of CM due to D. hominis which seems to have been acquired from an indigenous source.

Case Report:
A nine-years-old Sudanese female, from Gedaref area, Eastern Sudan, complained of an unexplained discharging furuncular skin lesion on her right leg for two weeks. She sought medical advice several times and was given topical treatments and oral antibiotics. The patient was referred to Tropical Diseases Teaching Hospital (TDTH), Omdurman, because a larva dropped from the lesion while the patient's mother was dressing it. The larva was identified as D. hominis at TDTH (The figure). The patient was reassured and no specific treatment was given.

Discussion:
CM is more common among children in rural areas, and our case goes with this trend 7 . Myiasis can be transmitted from animal to man, and had been described in animals from different parts of the world including Sudan 8,9 . We have previously reported one human CM case from Taif region, western Saudi Arabia 1 . In the present case there was no history of travel abroad, and we suggest the source of infection to be domestic animals. Early diagnosis of CM is important to save the patient undue anxiety and to avoid prescription of unjustified drugs. CM represents an association between man and ectoparasites 10 . It is relatively simple to manage a single incident of D. hominis infestation, however understanding of the biology and epidemiology of this organism is necessary for prevention of CM at community level.
Ascites is not necessarily an ominous sign in women with a pelvic tumour Salah Ismail Abdelrahman,MD 1

. Elfadil Moh Elnagar MGO 2
Ovarian cancer may progress from early to advanced stages within relatively a short period. Early symptoms are often vague and may resemble those of less serious conditions, such as menstrual disorders and intestinal illnesses. Ovarian cancer is called the silent killer because it progresses almost silently. By the time symptoms appear, the ovarian tumour may have grown large enough to shed cancer cells throughout the abdomen and metastasize in the chest. Ultrasound, CT-scan, MRI, and tumour markers usually suggest presence of a pelvic tumour but do not indicate reliably whether it is benign or malignant 1,2,3 .
The association of a benign ovarian tumour with ascites and hydrothorax that resolve after tumour resection is known as Meigs' syndrome. It usually occurs in elderly females. It was first emphasized by Meigs and Cass in 1937 4,5 . The importance of Meigs' syndrome is that the presence of ascites and pleural effusion does not necessarily indicate that a pelvic mass is malignant. The benign tumours in Meigs' syndrome are usually fibromas or fibrothecomas which constitute 4% of all ovarian neoplasms 1,6 . Here we describe a case of pelvic tumour in a young female.

Case report
A 28-year old single female from Gadarif Eastern Sudan, presented to Saad Abo el Ela Teaching Hospital with chest pain, dry cough and abdominal swelling for two months On examination she was rather ill, not jaundiced, cyanosed or tachypnoic. Pulse 78/min, BP 110/65mmHg, RR 16/min. There was diminished air entry more marked at the right side of the chest with clear stony dullness on percussion denoting presence of significant amount of pleural effusion. At examination of the abdomen a pelvi-abdominal mass, firm in consistency, rounded in shape, freely mobile with irregular surface was palpated. Vaginal examination was not possible because she was virgin. Investigations; Hb 11gm/dl, urinalysis was clear. ESR 45mm first hour. Chest x-ray (Fig 1) confirmed the presence of pleural effusion more marked on the right side, no evidence of parenchymal lung disease or metastases. Ultrasonic scan showed a huge mass in pelvic cavity 16.2 X10.2 cm in diameter, the uterus was normal in size and shape but there was free fluid in the peritoneal cavity and free fluid in right pleural cavity. Preliminary diagnosis of Meigs' Syndrome was made and the patient was prepared for laparotomy.  During surgery a solid irregular right ovarian mass was found, with large amount of free fluid in the peritoneal cavity, but no evidence of infiltration of the adjacent organs, liver or peritoneal metastasis. Sample of the ascetic fluid was taken for cytology and the rest of the fluid was sucked out. The mass was resected and sent for histopathology (Fig 2).

Cytology of the ascitic fluid revealed no abnormality
Histopathology made a diagnosis of fibroma of the ovary. The postoperative period was uneventful. The patient was discharged home and followed in the out patient department. The pleural effusion and ascites subsided and disappeared in four weeks time (Fig 3).

Discussion:
Meigs' syndrome is characterized by solid ovarian tumour, usually fibroma, associated with ascites and hydrothorax 4 . It occurs mainly in elderly women 4,7 . Pseudo-Meigs' syndrome (a term given by Meigs) is the same as true Meigs' syndrome, except that in the pseudo-Meigs' syndrome the tumour may be in the ovary, tubes, uterus or round ligament. The first report of this condition involved Dame Mary Page, wife of Sir Gregory Page, Bunhill Fields, England, who died in 1728, in her 56 th year. Otto Spiegelberg (1830-1881) in 1866 described a patient with fibroma, ascites, and hydrothorax, and erroneously concluded that the diagnosis was "ovarian pregnancy." In 1879 Charles James Cillingworth (1841-1908) in 1887, Albert Jean Octave Demons (1842-1920) of France in 1892, Robert Lawson Tait (1845-1899) of England followed by P. Pascale and Louis Félix Terrier (1837-1908) in 1888 described some forms of Meigs' syndrome. Meigs 4 described the condition in 1934, and with John W. Cass 5 in 1937 described it as a syndrome comprising ovarian fibroma, ascites and hydrothorax. Their first report disclosed details of seven cases collected during the years 1901-1934, as well as discussion of the syndrome. In the same year 1937, J. E. Rhoads and A. W. Terrell 8 described another case, and these authors termed the condition Meigs' syndrome. Meigs' syndrome is also known as: Demons-Meigs' syndrome, Meigs-Cass syndrome.
Ascites in Meigs` syndrome may be due to local irritation by solid pelvic mass, or secretion of vaso-active mediators by the tumour 9 . However, the fluid may pass through the diaphragmatic defects or lymphatic channels to form pleural effusion 10 .
Many ladies complain of abdominal pain and swelling months before they are diagnosed with ovarian neoplasm. Ovarian cancers are potentially life-threatening malignancies that develop in one or both ovaries. Malignant ovarian tumours generally fall into three primary classes: Epithelial tumours (90%), germ cell and stromal tumours Meigs' syndrome typically occurs in elderly females. However, rare cases of Meigs' and PseudoMeigs' syndrome were reported in few young females 11,12 and unmarried females like our patient 11 .
Although clinically Meigs' syndrome looks typical to ovarian cancer, inherited genetic factors as BRCA1 and 2 or other genetic mutations that play a role in ovarian cancer do not have any impact on pelvic tumours of Meigs' syndrome. Also, the genetic alterations that have been observed in ovarian cancers as p53 tumour suppressor gene, HER2/neu gene, and PIC3KA gene and the ethnic factors were not reported to have any roll in the aetiology of tumours in Meigs' syndrome. On the other hand, women who have never had children are more likely to develop ovarian cancer than women who have reduced ovulations because of repeated pregnancies, lactations or use of birth control pills that contain the female hormones estrogen and progestin. This latest fact seems to be consistent with our patient and some other cases of reported as Meigs' syndrome 11 .
These comparisons are important because of the clinical similarities between malignant and benign ovarian tumours. In addition, CA-125 which is a protein secreted by ovarian cancer cells is elevated in over 80% of patients with ovarian cancer is found to be highly elevated in the majority of the benign Meigs' tumours2, 12,14,15. Though the CA-125 blood test is not approved for screening in the general population in both conditions, oncologists usually obtain a blood test for this protein if ovarian cancer is strongly suspected but if it turn to be high it does not confirm the presence of malignancy because it is usually high in benign tumours of Meigs' syndrome. So, it is not a reliable preoperative test for diagnosis.
Therefore, any female complaining of vague abdominal pain and/or feeling of abdominal swelling (usually caused by fluid or mass within the abdomen), pelvic pressure or cramps, digestive problems such as gas, bloating, bowel and bladder problems such as constipation and frequent urination, loss of appetite or feeling of fullness even after a very light meal, unusual vaginal bleeding, back pain or leg pain should be thoroughly examined and investigated. However, neither ultrasound examination nor computed tomography or MRI can reliably offer a preoperative diagnosis. All do not provide enough specific information to reliably determine which abnormal masses are cancerous or noncancerous. It is also important to remember that a pelvic neoplasm in a woman presenting with hydrothorax, ascites, and elevated CA 125 levels might be benign and that this condition may rapidly be resolved with surgical removal 1, 2 .
In order to establish a prognosis and determine treatment, the doctor needs to know the cell type, stage, and grade of the disease. This is why surgery should not be denied and it will not be astonishing to end with a final diagnosis of Meigs's syndrome due to fibroma 1,7,15,16 or thecoma of the ovary 17 or Pseudomeigs' syndrome due to a benign pathology such as leiomyoma with focal hyaline and extensive hydropic degeneration 18 , leiomyoma with parasitized blood supply from the omentum 19 , leiomyoma of the ovary 20 , utrine leiomyoma 21,22,23,24 , benign Brenner tumours 25 ovarian hemangioma 26 , granulosa cell tumour 27 , dysgerminoma 28 , struma ovarii a specialized ovarian teratoma composed predominantly of mature thyroid tissue 29, 30, 31 , benign mature teratoma 11 , or malignant disease as malignant struma ovarii 32 and secondaries from carcinoma of stomach (Krukenberg tumors ) 33 , colon 34 or epithelial cell ovarian cancer 35 , and malignant mixed germ cell tumour of the ovary 36