Inflammatory, Hypersensitivity and Immune Lung Diseases, including Parasitic Diseases.
Fred W Wright in Radiology of the Chest and Related Conditions, 2022
Filariasis - three forms are of medical importance - Loa-Loa, Wucheria bancrofti and Onchcercosis. Worms in this group produce microfilariae, which undergo maturation in an insect (often the mosquito, especially Culix fatigans) and are thence transferred to man. Loa-Loa worms are transferred by horse-flies and may produce small calcified nodules 'Calabar swellings' (named after a town in Nigeria). The filarial worms tend to lodge in regional lymph nodes and cause lymphatic obstruction by mechanical means when they are present in large numbers, and by inflammatory reaction when they die and disintegrate. The affected nodes enlarge and contain dilated sinusoids, the nodal obstruction causing dilatation of more peripheral lymph vessels and lymphoedema and 'elephantiasis'. A novel way of diagnosing the condition is to use scrotal ultrasound when dilated lymphatics (sometimes containing wriggling live worms) may be seen (Dreyer et al., 1994). Chylothoraces and thoracic duct obstruction are discussed on p. 14.10. Filariasis may also lead to endomyocardial fibrosis.
Parasites
Thomas T. Yoshikawa, Shobita Rajagopalan in Antibiotic Therapy for Geriatric Patients, 2005
Common causes of fixed, painful subcutaneous swellings include myiasis, tungiasis, and furuncles. Myiasis is caused by invasion of the skin by the larvae of diptera (flies), including Cordylobia anthropophaga (the tumbu fly) in Africa and Dermatobia hominis (the botfly) in Latin America. Myiasis lesions resemble boils but have a central opening through which serosanguinous material oozes and through which the larvae may emerge (Fig. 1, panel D). Patients often report intermittent pain and a sensation of movement in the area of the lesion. Tungiasis (also known as jiggers), seen in travelers returning from Latin America, Africa, or India, develops after the female sand flea, Tunga penetrans, invades the skin, often around the toenails and soles (Fig. 1, panel E). Infection with Loa loa may become evident years after exposure as eyeworm or as migratory areas of angioedema (Calabar swellings),
Ivermectin
Sarah H. Wakelin, Howard I. Maibach, Clive B. Archer in Handbook of Systemic Drug Treatment in Dermatology, 2015
Other uses: oral ivermectin has been successfully used to treat orbital and nasal myasis, scalp pediculosis and Demodex folliculitis. It is safe and effective against ocular Loa Loa; however, individuals with high parasitic loads are at risk of developing severe neurological reactions after simultaneous treatment with ivermectin and diethylcarbamazine (DEC). Ivermectin has been found to decrease adult survival, fecundity and hatch rate of eggs in Aedes aegypti mosquitoes and appears to have similar effects in Anopheles, the human malaria vector. Interest has therefore grown regarding its role as a complementary strategy in malaria eradication. Benefit has also been reported in treatment of other soil transmitted helminth infections and gnathostomiasis. An antiviral effect in human immunodeficiency virus (HIV), and cell death in leukaemia cell lines from humans and rodents have also been demonstrated.
Relationships between T-scores at the hip and bone mineral density at the distal femur and proximal tibia in persons with spinal cord injury
Published in The Journal of Spinal Cord Medicine, 2020
Christopher M. Cirnigliaro, J. Scott Parrott, Mary Jane Myslinski, Pierre Asselin, Alexander T. Lombard, Michael F. La Fountaine, Steven C. Kirshblum, Gail F. Forrest, Trevor Dyson-Hudson, Ann M. Spungen, William A. Bauman
The Bland–Altman analysis was used to examine agreement between predicted and measured values based on the linear regression equations obtained. A small mean difference (bias) between the predicted and measured values was observed for all regions (<0.1 SD). Analysis of the 95% CI limit of agreement (LOA) using the DF and PT to predict T-scores ranged from −1.991 to 1.990 and −1.938 to 1.939 at the TH, respectively, (Fig. 2 A and B, light dashed lines) and −1.825 to 1.827 and −1.770 to 1.770 at the FN, respectively (Fig. 2 C and D, light dashed lines). For TH and FN regions, the regression estimates from the DF and PT predicted between 93 and 94% of the total sample of T-scores (Fig. 2 A-D). A second clinically relevant LOA (LOAclin) was set at the acceptable threshold (±1 SD) with the DF and PT accurately predicting 75% and 71% of TH T-score values, respectively, and 76% of FN T-score values, respectively (Fig. 2 A-D). Despite the overall good levels of agreement between the difference and measured values, when the predicted and observed T-score values are outside the 95% limit of agreement, the predicted T-score values are lower than the measured T-score values, overestimating the measured values between −2.0 and −4.0 SD, evidence that measures at the hip and knee region should be obtained separately in populations with a high prevalence of osteoporosis that are at increased risk for fracture.
Moxidectin: an oral treatment for human onchocerciasis
Published in Expert Review of Anti-infective Therapy, 2020
Philip Milton, Jonathan I. D. Hamley, Martin Walker, María-Gloria Basáñez
To date, no study has been conducted to investigate the safety of using moxidectin in O. volvulus–Loa loa co-infected individuals. Ivermectin can cause SAEs, including potentially fatal encephalopathy, in individuals with high L. loa microfilaremia [72]. The pathophysiology of such SAEs is poorly understood but it appears to have an immunological basis, involving interleukin (IL)5-driven eosinophilia and eosinophil activation (positively correlated with pre-treatment microfilarial count) in the mechanism of microfilarial killing by ivermectin in loiasis [73]. Given moxidectin’s strong microfilaricidal effect and overall similarity to ivermectin, it will be crucial to determine the safety of moxidectin for the treatment of onchocerciasis in loiasis co-endemic areas, its efficacy for the treatment of loiasis, and the immunological mechanisms involved in the killing of L. loa microfilariae and any subsequent AEs.
An unexpected peripheral blood finding: microfilaria
Published in Baylor University Medical Center Proceedings, 2020
John R. Krause, Meleissa Hutcheson, Rebecca Ardoin
The roundworm in our patient was Mansonella perstans, one of the three filarial species in the genus Mansonella (the other two being M. ozzardi and M. streptocerca), which are included in the category of serous cavity filariasis. In mammalian hosts, adult Mansonella worms are located in connective tissues or peritoneal, pleural, or pericardial cavities.4 Microfilaria of M. perstans will circulate in the blood and are approximately 190 to 200 μm in length × 4 μm (slightly smaller than the diameter of a red blood cell). The microfilariae are unsheathed; the tail tapers to a bluntly rounded end and nuclei extend to the end of the tail.5 Because the microfilariae are small, they can be overlooked in blood films. In the blood, they may be distinguished from other sympatric microfilariae including Loa loa or Wuchereria bancrofti, which are longer and sheathed and have larger terminal nuclei.5
Related Knowledge Centers
- Conjunctiva
- Microfilaria
- Onchocerca Volvulus
- Subcutaneous Tissue
- Onchocerciasis
- Loa Loa Filariasis
- Neglected Tropical Diseases
- Filariasis
- Mansonella Streptocerca
- Host