RESUMO
PURPOSE: Human ophthalmomyiasis is a rare ocular parasitosis that results from the accidental infestation of dipteran larvae of several species, including Oestrus ovis (Linnaeus, 1758). This study aims to present the fourth documented human case of ophthalmomyiasis in Mexico, identifying the etiological agent through morphological and molecular analyses. Additionally, we investigated the phylogenetic position and genetic distances among different specimens globally characterized based on mitochondrial Cox1 sequences. METHODS: A total of five larval specimens were extracted from the patient's eye, with two specimens allocated for identification based on morphological features using a stereomicroscope, and the remaining three preserved in absolute ethanol, one of them used for subsequent analysis using molecular methods. The mitochondrial Cox1 region was amplified and sequenced using automated Sanger sequencing. The resulting sequence was deposited in GenBank under accession number OR440699 and subjected to BlastN analysis against 35 other Cox1 sequences of O. ovis from GenBank. The identity and phylogenetic position of the strains were further explored using parsimony and maximum likelihood phylogenetic methods. RESULTS: Morphological examination of the larval specimens extracted from the patient's eye unequivocally identified them as O. ovis species. BlastN analysis and comprehensive phylogenetic investigations involving a total of 36 Cox1 sequences confirmed the taxonomic identity of the larvae. Notably, our sequence was positioned within the cluster formed by the Brazilian and two Iranian samples. This finding underscores a shared genetic ancestry among these distinct geographical isolates and provides valuable insights into the evolutionary relationships within O. ovis populations. CONCLUSION: The presence of O. ovis infestation in Mexico City suggests potential shifts in environmental conditions favoring fly proliferation, highlighting the need for vigilance in urban healthcare settings.
Assuntos
Dípteros , Infecções Oculares Parasitárias , Larva , Miíase , Filogenia , Animais , Miíase/parasitologia , Miíase/veterinária , Larva/genética , Larva/classificação , México , Humanos , Dípteros/genética , Dípteros/classificação , Dípteros/parasitologia , Infecções Oculares Parasitárias/parasitologia , Infecções Oculares Parasitárias/veterinária , Infecções Oculares Parasitárias/diagnóstico , Masculino , FemininoRESUMO
OBJECTIVE: This review aims to describe and compare the risk factors, clinical course, diagnosis, and parasitologic features of external ophthalmomyiasis. We also discuss the different preventive measures and the effect of global warming in a large case series reported from January 2000 to December 2022. METHODS: We perform a literature review of reported cases of external ophthalmomyiasis to determine the clinical characteristics, therapeutic management, and information on the organisms that most commonly cause external ophthalmomyiasis. RESULTS: A total of 312 cases of external ophthalmomyiasis were recorded. The most common causative organism was Oestrus ovis (Linnaeus) (Diptera: Oestridae), accounting for 72.1% of cases, followed by Dermatobia hominis (Linnaeus Jr. in Pallas, 1781) (Diptera: Oestridae) at 5.4%, Lucilia sericata (Meigen) (Diptera: Calliphoridae) at 0.96%, and Chrysomyia bezziana (Villeneuve) (Diptera: Calliphoridae) at 0.96%. Before experiencing symptoms, 43.6% of cases reported having direct contact with flies or being hit in the eye, 33% reported no associated risk factors, 9.3% reported living with sheep and goats, and 7.7% reported a history of foreign objects entering the eye. The most common symptoms for those affected by O. ovis were sudden onset, including a foreign body sensation and movement, redness, tearing, itching, swelling, irritation, photophobia, burning, and ocular secretion. In cases caused by D. hominis, symptoms included eyelid edema, pain, redness, itching, movement within the lesion, ocular irritation, and discharge. Regarding occupational or recreational activity, agriculture, and livestock had the highest incidence, followed by trades and technical activities, being a student, and having traveled to an endemic region for work or recreation. CONCLUSION: Patients with red eyes may suffer from external ophthalmomyiasis, which requires a thorough examination to diagnose and treat it early. Moreover, as the temperature increases due to climate change, it is essential to consider how this will affect the spread of different pathogens.
RESUMO
We present the case of a young male patient who presented with pain, redness and foreign body sensation in his left eye. There was no associated decrease in vision. Three live larvae were removed from his left conjunctival sac and sent to the laboratory for identification. The patient was treated symptomatically and his symptoms were mostly resolved by the following day. The larvae were later identified as the first instar of the sheep nasal botfly. Poor sanitation and exposure to livestock were among the identified risk factors in this case. Physicians must have this as a differential diagnosis for conjunctivitis in patients with risk factors. This is the first reported case of ophthalmomyiasis from Jamaica.
Assuntos
Conjuntivite/diagnóstico , Dípteros/fisiologia , Infecções Oculares Parasitárias/diagnóstico , Miíase/diagnóstico , Adolescente , Animais , Conjuntivite/parasitologia , Diagnóstico Diferencial , Infecções Oculares Parasitárias/parasitologia , Infecções Oculares Parasitárias/terapia , Humanos , Jamaica , Larva/citologia , Masculino , Miíase/parasitologia , Miíase/terapia , Fatores de Risco , Resultado do TratamentoRESUMO
CLINICAL CASE: A 46-year-old woman with no relevant medical history, native of Honduras and resident in Spain for one and a half months. The patient went to the Emergency Department due to inflammation of the upper eyelid of the right eye, with an area that simulated an abscess. This was drained (obtaining hardly any purulent content). Treatment was prescribed with oral and topical antibiotics, as well as an anti-inflammatory drug. One week later the patient returned, with improvement of the inflammatory signs, but with discomfort and corneal erosions. After eversion of the upper eyelid, a «worm¼ type parasite emerged from the tarsus. The extraction was completed with a clamp, and was later identified as Dermatobia hominis (Dh) by examination of a fresh specimen. The subsequent outcome of the patient was favourable. DISCUSSION: Preseptal cellulitis in patients from tropical and sub-tropical areas can be caused by Dh.