Imaging as a (pre)clinical tool in parasitology.

Imaging of parasites is central to diagnosis of many parasitic diseases and has thus far played an important role in the development of antiparasitic strategies. The development of novel imaging technologies has revolutionized medicine in fields other than parasitology and has also opened up new avenues for the visualization of parasites. Here we review the role imaging technology has played so far in parasitology and how it may spur further advancement. We point out possibilities to improve current microscopy-based diagnostic methods and how to extend them with radiological imaging modalities. We also highlight in vivo tracking of parasites as a readout for efficacy of new antiparasitic strategies and as a source of fundamental insights for rational design.

Endemic Thoracic Infections in Sub-Saharan Africa.

Although many of the thoracic infections endemic to Africa are also present around the world, this article focuses on entities that are emerging or disproportionately affect populations living in sub-Saharan Africa. Important emerging or reemerging viral and bacterial diseases that commonly affect the lung include dengue fever, plague, leptospirosis, and rickettsioses. Most parasitic infections endemic to Africa can also manifest within the thorax, including malaria, amebiasis, hydatid disease, schistosomiasis, paragonimiasis, ascariasis, strongyloidiasis and cysticercosis. Level of sanitation, interaction between humans and host animals, climate change, political instability, and global travel all affect the distribution and burden of these diseases.

A French case of porocephalosis diagnosed by radiologists.

Porocephalosis is the name given to human infection by Armillifer, which is rare, especially in European and North American populations. Among the few cases reported to date, most of them were described in the African community. Humans can become infected, for example, consuming undercooked meat from infected snakes. Herein we report the case of a 31-year-old male, originally from the Democratic Republic of the Congo, who was living in France for many years and presented with lower back pain and mild abdominal pain. Imaging showed multiple comma-shaped calcifications disseminated in the liver and the peritoneal cavity, without any additional feature. The patient reported regular consumption of snake meat during his travels in Africa, and thus the diagnosis of porocephalosis could be made. Doctors treating patients from endemic areas or traveling in endemic areas, particularly in Africa, should become familiar with this infection and consider it in the case of multiple calcifications on imaging. More cases of porocephalosis are likely to be seen in the future because of the increase in international travel.

Pictorial Review of Thoracic Parasitic Diseases: A Radiologic Guide.

Parasitoses are infectious diseases of global distribution, with predominance in areas of poor sanitation. Parasites cause damage through direct tissue injury and the inflammatory response generated by their migration and establishment in various organs. Thoracic involvement by parasitic disease can generate both specific and nonspecific clinical, laboratorial, and radiologic manifestations, which often makes their diagnosis challenging. The correct diagnosis is crucial for definition of treatment, which sometimes requires rapid intervention. Based on a literature review of the last few decades, this article aimed to characterize the main radiologic findings related to thoracic manifestations of parasitic diseases, correlating them with radiographic and tomographic images of patients with confirmed diagnosis of such pathologies. The included parasitic diseases are malaria, Chagas disease, toxoplasmosis, amoebiasis, ascariasis, toxocariasis, strongyloidiasis, dirofilariasis, cysticercosis, echinococcosis, schistosomiasis, and paragonimiasis.

Parasitic Liver Infections: Imaging Findings and Strategies for Timely Diagnosis.

There are a number of parasitic infections that can affect the liver and biliary tree. These infections can be primarily related to the liver or can include secondary hepatic involvement. Imaging can narrow down the differential diagnosis in the appropriate clinical setting, and can even clinch the diagnosis with some pathognomonic findings. The various imaging modalities can also identify disease extent, help guide management, and demonstrate response to treatment. This pictorial essay will give an overview of parasitic liver infections, and will discuss the best imaging strategies and the key imaging features to help make a timely accurate diagnosis.

A case of human pancreatic eurytremiasis.

This study provides the first comprehensive imaging report of human pancreatic eurytremiasis. A 43-year-old man with obstructive jaundice and a pancreatic tumor was referred for diagnosis and treatment. Serum aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transpeptidase were elevated. Computed tomography (CT) revealed a multilocular cystic lesion with delayed enhanced area in the pancreas head. On magnetic resonance imaging, the tumor was hyperintense on diffusion-weighted image, and the apparent diffusion coefficient value of the tumor was lower than that of the normal pancreatic parenchyma. Positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography (18F-FDG PET/CT) revealed abnormally increased uptake of 18F-FDG in the tumor. A subtotal stomach-preserving pancreaticoduodenectomy was performed on the preoperative diagnosis of pancreatic carcinoma accompanied by branch duct-type intraductal papillary mucinous neoplasm. Multifocal granulomatous lesions with necrotic areas including many parasite eggs were seen on the histology. The final diagnosis was pancreatic eurytremiasis.

Sound Around the World: Ultrasound for Tropical Diseases.

Ultrasound for diagnosis and staging of schistosomiasis and echinococcosis have paved the way over the past several decades for the application of ultrasound in tropical diseases. Until recently, the size and cost of ultrasound systems limited the application in low-resource settings. The increase in portable ultrasound systems has given more clinicians access to ultrasound, and clinically based protocols for the care of patients have emerged, such as focused assessment with sonography for HIV/TB and tropical cardiac ultrasound. This article explores the history and current use of ultrasound in these diseases and highlights their application in the care of patients.

Point-of-Care Ultrasound in Resource-Limited Settings: Common Applications.

Point-of-care ultrasound (POCUS) is used increasingly in resource-limited settings (RLSs), particularly as inexpensive ultrasound machines and evidence-based protocols become more available. POCUS often is the only imaging modality available in such settings, and it has the potential to significantly affect patient care. This article discusses four case-based reviews of POCUS in RLSs for several common diseases: pediatric pneumonia; extrapulmonary tuberculosis; ectopic pregnancy; and tropical parasitic diseases, including echinococcus, schistosomiasis, and amebiasis. It concludes with a discussion of the logistical considerations specific to implementing POCUS in RLSs, particularly equipment and training. The literature reviewed suggests that POCUS has the potential to improve the diagnosis and management of multiple conditions in RLSs, although further research is needed.

Chronic Cavitary Infections Other than Tuberculosis: Clinical Aspects.

Lung cavitation may be due to infectious or noninfectious pathologic processes. The latter category includes nonmalignant conditions, such as granulomatosis with polyangiitis, and malignant conditions, such as squamous cell carcinoma of the lung. Infectious etiologies that produce lung cavitation usually cause chronic illness, although some, particularly pyogenic bacteria, may produce acute cavitary disease. Tuberculosis is the most common cause of chronic pulmonary infection with cavitation. The goal of this review was to highlight a selection of the better-known infectious agents, other than tuberculosis, that can cause chronic lung disease with cavitation. Emphasis is placed on the following organisms: nontuberculous mycobacteria, Histoplasma, Blastomyces, Coccidioides, Paracoccidioides, Aspergillus, Burkholderia pseudomallei, Paragonimus westermani, and Rhodococcus equi. These organisms generally produce clinical features and radiologic findings that overlap or mimic those of tuberculosis. In a companion article, we have further emphasized aspects of the same conditions that are more pertinent to radiologists.

A Case of Pentastomiasis at the Left Maxilla Bone in a Patient with Thyroid Cancer.

Pentastomiasis, a zoonotic parasite infection, is typically found in the respiratory tract and viscera of the host, including humans. Here, we report for the first time an extremely rare case of intraosseous pentastomiasis in the human maxilla suffering from medication related osteonecrosis of the jaw (MRONJ). A 55-year-old male had continuously visited the hospital for MRONJ which had primarily developed after bisphosphonate and anti-neoplastic administration for previous bone metastasis of medullary thyroid cancer. Pain, bone exposure, and pus discharge in the right mandible and left maxilla were seen. Osteolysis with maxillary cortical bone perforation at the left buccal vestibule, palate, nasal cavity, and maxillary sinus was observed by radiologic images. A biopsy was done at the left maxilla and through pathological evaluation, a parasite with features of pentastome was revealed within the necrotic bone tissue. Further history taking and laboratory evaluation was done. The parasite was suspected to be infected through maxillary open wounds caused by MRONJ. Awareness of intraosseous pentastomiasis should be emphasized not to be missed behind the MRONJ. Proper evaluation and interpretation for past medical history may lead to correct differential diagnosis and therapeutic intervention for parasite infections.

Colonic Parasitic Infection Mimicking Peritoneal Seeding on 18F-FDG PET/CT.

A 77-year-old man with anorexia and weight loss for 6 months received a diagnosis of gastric cancer by endoscopy and referred for F-FDG PET/CT for initial staging. F-FDG PET/CT showed multiple foci of increased FDG uptake with diffuse wall thickening and multiple diverticula. The differential diagnoses were peritoneal seeding and multiple diverticulitis. The patient underwent curative total gastrectomy, and the lesion was diagnosed as poorly differentiated adenocarcinoma by histological examination. He underwent anterior resection of the sigmoid colon for exploration. The nodular lesions of the sigmoid colon were diagnosed by histopathologic examination as chronic diverticulitis caused by a parasitic infection.

Imaging of the Pancreas.

The evaluation of pancreatic lesions, from solid pancreatic masses to pancreatic cysts, remains a clinical challenge. Although cross-sectional imaging remains the cornerstone of the initial evaluation of an indeterminate pancreatic lesion, advances in imaging with the advent of endoscopic ultrasound scan, elastography, contrast-enhanced endoscopic ultrasound scan, and probe-based confocal laser endomicroscopy have allowed us to visualize the pancreas in even higher resolution and diagnose premalignant and malignant lesions of the pancreas with improved accuracy. This report reviews the range of imaging tools currently available to evaluate pancreatic lesions, from solid tumors to pancreatic cysts.

Armillifer armillatus infestation in Human; public health scenario of a snake parasite: a report of three cases.

We report cases of Armillifer Armillatus infestation in three Nigerian adults within two and half years in our health facility. The first patient was a 70 year old farmer and a regular consumer of snake meat for over 50 years. He presented in February, 2014 for follow-up visit as he was a known systemic hypertensive patient. He was incidentally discovered to have multiple comma-shaped calcific lesions in the lungs and liver on a chest radiograph. These were better demonstrated on abdominal ultrasound and computed tomographic scans. He was asymptomatic. The second patient was a 42 year old male civil servant who presented in December 2015 with dry cough and right loin pain for five and three days respectively. His past medical history revealed that he had been treated previously for pneumonia. He has never eaten snake meat but consumed Alligator (Amphibious reptile) for many years but stopped about 12 years ago. Similar calcific lesions were also noted in his liver and lung parenchyma on chest radiograph and abdominal ultrasound scan. The third patient was an 80 year old man who presented in April, 2014 with dizziness and diminished urine output of one day duration. He was a farmer who has been consuming snake meat for many years, and has been on management for systemic arterial hypertension and prostatic hypertrophy. Chest radiograph and abdomino-pelvic ultrasound incidentally revealed multiple comma-shaped calcific lesions in the lungs and liver. The liver function test parameters were all within normal limits but the electrolytes were deranged and he was anaemic with a Packed Cell Volume of 27%. A diagnosis of Armillifer Armillatus infestation was made in these patients, and they were conservatively managed with Mebendazole. The third case was catherized and the deranged electrolytes were corrected. The first patient was lost to follow-up, whiles the second and third had no remarkable symptoms on subsequent follow-up visits.

Parasitic and rare spinal infections.

The imaging features of spinal parasitic diseases and other rare infections are herein discussed. These diseases are distributed worldwide, with increased prevalence in areas with poor sanitary conditions and in developing countries. In nonendemic areas, sporadic cases may occur, consequent to increased international travel and immunocompromising conditions. Infectious diseases are usually treatable, and early detection is often crucial. A thorough comprehension of the imaging patterns associated with the clinical features, epidemiology, and laboratory results allows the radiologist to narrow down the options for differential diagnosis and facilitates the timely implementation of appropriate therapies.

Mammographic parasitic calcifications in South West Nigeria: prospective and descriptive study.

INTRODUCTION: Lymphatic filariasis caused by nematode parasite Wuchereria bancrofti and Brugia Malayi is endemic in the tropics. In Nigeria, 25% of the population is infected. Lymph edema and elephantiasis are the predominant manifestations. Its infrequent manifestation is in the breast. This paper discusses the epidemiology, reviews literature, imaging options and mammographic appearances of these parasitic nematodes. METHODS: This prospective descriptive study reports on 39 cases of parasitic calcifications seen during mammography in the Radiology Department, University College Hospital between 2006 and 2012 in Ibadan, South West Nigeria. Each mammogram was reported by MO and ATS: assigned a final Bi-RADs category. Parasitic calcifications were further evaluated for distribution, and types of calcification. RESULTS: A total of 527 women had mammography done between 2006 and 2012. Thirty-nine women (7.4%) had parasitic breast calcifications. The ages of the women ranged between 38-71 years--mean of 52.36±8.72 SD. Twenty-three (59%) were post-menopausal, 16(41%) were pre-menopausal. The majority (31; 79.5%) were screeners while 8(20.5%) were follow up cases. Approximately half (51.3%) of the women had no complaints. Pain (23.1%) was the commonest presentation in the remaining half. Solitary calcifications were predominant (20) while only 3 cases had 10 calcifications. Left sided calcifications (53.8%) were the majority. Calcifications were subcutaneous in 2/3rds of the women (66.7%) while the Yoruba tribe (84.6%) was principal. CONCLUSION: Parasitic breast calcifications can be misdiagnosed on mammography for suspicious micro-calcification. This publication should alert radiologists in a tropical country like Nigeria to increase diagnostic vigilance thereby preventing unnecessary anxiety and invasive work-up procedures.