State-of-the-Art Review: Evaluation and Management of Delusional Infestation.

Delusional infestation is a condition encountered frequently by healthcare professionals across a variety of specialties in which patients have a fixed, false belief that they are infested with living creatures, such as bugs, parasites, worms, or mites, or nonliving objects, such as fibers. Delusional infestation can be debilitating for patients, who not only present with intense psychological distress and physical discomfort but are also at risk of developing numerous dermatological and psychiatric complications. This condition poses unique diagnostic challenges, as these symptoms can occur secondary to many metabolic or infectious causes, as well as unique treatment challenges, with patients frequently refusing psychiatric care and consequently seeking evaluation by other healthcare professionals. In this review, we aim to use existing literature to provide clinicians in infectious diseases or other specialties with sufficient clinical context and treatment guidance for the appropriate management of delusional infestation.

Morphologic and Molecular Identification of Human Ocular Infection Caused by Pelecitus Nematodes, Thailand.

Nematodes of the Onchocercidae family, such as Pelecitus spp., are filarial parasites of medical and veterinary importance. Although infections are widely distributed among avian species, only 2 cases of human Pelecitus ocular infection, both in South America, have been reported. We describe a 61-year-old man in northeast Thailand diagnosed with an ocular infection. Morphologic characteristics suggested the causative agent was a female Pelecitus nematode: coiled body, rounded anterior and posterior extremities, a distinct preesophageal cuticular ring, lateral alae, a postdeirid, and a protuberant vulva. Sequences of the 12S rDNA gene indicated 95%-96% identity and cox1 gene 92%-96% identity with published P. copsychi sequences. P-distance for cox1 sequences between the causative agent and P. copsychi was 6.71%. Phylogenetic trees of 12S rDNA and cox1 genes indicated the species differed from but is closely associated with P. copsychi. Healthcare providers should be aware of the threat of ocular infection from Pelecitus spp. nematodes.

From evidence to practice: A systematic review-based diagnostic algorithm for paediatric eosinophilia across socioeconomic context.

AIM: Paediatric eosinophilia is a common clinical dilemma, often leading to resource- and time-consuming assessments. We aim to evaluate the main aetiologies of eosinophilia in children from different socioeconomic settings and propose a diagnostic algorithm. METHODS: A systematic literature review was conducted through PubMed, Embase and the Cochrane Library. Studies published from January 2012 to June 2023 reporting the incidence and aetiology of peripheral eosinophilia in children were included. Evidence from studies on children originating from low- or high-income countries was compared. RESULTS: A total of 15 observational studies, encompassing 3409 children, were included. The causes of eosinophilia varied based on the children's origin and the eosinophilia severity. In children from high-income countries, allergic diseases were the leading cause, with a prevalence of 7.7%-78.2%, while parasitosis ranged from 1.0% to 9.1%. In children from low-income countries, parasitosis was predominant, ranging from 17.7% to 88.3%, although allergic diseases were found in 2.5%-4.8% of cases. Concerning severity, allergic diseases were the leading cause of mild-to-moderate eosinophilia; parasitosis was associated with moderate-to-severe eosinophilia, while immunological disorders were mostly found in severe cases. CONCLUSION: We developed a step-up diagnostic algorithm that considers the child's origin and eosinophilia severity and could optimise resource allocation.

Pathological, morphological, and molecular characterization of the infection by Brachycladium goliath in humpback whale Megaptera novaeangliae.

The humpback whale (Megaptera novaeangliae) is a cosmopolitan migratory, seasonal mysticete that frequents the Brazilian coast. Strands of specimens may occur during the migratory stay in the country. In 2021 and 2022, three live humpback whales stranded on the coast of Rio Grande do Sul and Santa Catarina states in southern Brazil. After euthanasia, specimens were necropsied, and organs were thoroughly examined for lesions. Grossly, in all three cases, the liver exhibited multifocal, irregular, firm, white areas on the hepatic capsule, which extended into the parenchyma. On the cut surface, the livers were yellow to pale brown with orangish to greenish areas, the bile ducts were prominent, thickened, and severely dilated, and leaf-shaped flukes were found inside of them. Additionally, one case showed moderate atrophy of the right hepatic lobe. The histological findings included dilation of bile ducts, hyperplasia of the bile duct epithelium, marked inflammatory infiltration of lymphocytes, plasma cells, and eosinophils, and portal fibrosis. The parasite Brachycladium goliath was both morphologically and molecularly identified based on diagnostic key for trematodes and the original description of the species, and the amplification and sequencing of the ITS-2 region, respectively. Even though hepatic injury was not the primary cause of stranding, it may have contributed to the debilitation of the whales. To the authors' knowledge, this is the first study that reports M. novaeangliae as a definitive host of B. goliath and that describes the lesions caused by the parasite in cetaceans.

Intraocular Parafilaria bovicola infection and surgical removal in a mixed breed heifer.

An approximately 1.5-year-old mixed breed heifer was presented for evaluation and treatment due to ocular pain affecting the right eye secondary to a live nematode within the anterior chamber. Ophthalmic examination revealed marked blepharospasm, evidence of chronic keratitis, uveitis, and a single, white, approximately 2.5 cm long, 0.5 mm thick, living parasite. The heifer underwent general anesthesia, and the parasite was removed using passive aqueous humor outflow following a stab incision into the anterior chamber. Twenty-four hours after removal of the intraocular parasite, the heifer displayed a significant improvement in ocular comfort, corneal edema, and uveitis. The nematode was identified via genetic analyses as Parafilaria bovicola, a filarial parasite of cattle. The heifer was discharged 5 days following nematode removal with a marked improvement in all ocular signs and apparently normal vision. To the authors' knowledge, there are no previous reports of confirmed intraocular filariosis caused by P. bovicola in the veterinary literature, nor are there reports detailing surgical removal of intraocular parasites in bovids.

Insights into the Medical Evaluation of Ekbom Syndrome: An Overview.

Ekbom syndrome, also known as delusional parasitosis (DP) or delusional infestation, is an uncommon psychiatric disorder distinguished by an enduring conviction of parasitic infestation, persisting notwithstanding the presence of medical evidence to the contrary. Primarily affecting middle-aged women, DP can manifest either as isolated psychological distress or as a component within a more intricate psychiatric framework, substantially influencing the quality of life for affected individuals. Its pathophysiological mechanism involves uncertain dopaminergic imbalances and dysfunction in the dopamine transporter system. Dermatologists often play a pivotal role in diagnosis, as patients first seek dermatological assessments of their signs and symptoms. However, DP frequently originates from underlying psychiatric disorders or medical variables, manifesting with neurological and infectious causative factors. The diagnostic complexity is attributed to patients' resolute convictions, leading to delayed psychiatric intervention. First-line DP treatment involves antipsychotics, with newer agents demonstrating promising prospects, but the lack of standardized protocols poses a significant therapeutic challenge. In this narrative review, both a comprehensive approach to this uncommon pathology and an update on the state of knowledge in this medical subfield focused on optimizing the management of DP are provided. The complexity of DP underlying its uncommon nature and the incomplete understanding of its pathophysiology highlight the need for further research through multicenter studies and multidisciplinary teams to enhance therapeutic efficacy and safety.

[Educational intervention as a prevention strategy for intestinal parasitosis, and assessment of the enteroparasitological status in child development centers in the city of Santa Fe, Argentina]. / Intervención educativa como estrategia de prevención de parasitosis intestinales y valoración del estado enteroparasitológico en centros de desarrollo infantil de la ciudad de Santa Fe, Argentina.

Intestinal parasitic diseases constitute a cosmopolitan public health concern, with greater prevalence in developing countries, and mainly affecting children. The aim of this study was to develop an educational intervention aimed at mothers/guardians of children attending three child development centers (CDI) in Santa Fe, Argentina, during 2018. An educational intervention was conducted using a descriptive, quasi-experimental design, with pre- and post-intervention assessment. This intervention included 36 mothers, and was carried out in three stages: diagnosis, intervention and final evaluation. Simultaneously, a coproparasitological study was performed on 48 children under 5 years of age, who were assisted in the CDI, with the aim to understand and address the parasitic infections prevalent in the child population. It was possible to compare the correct answers before and after the educational intervention, observing a statistically significant increase (p=0.008742) in the average number of correct answers. Enteroparasites were identified in 54% of the population of children analyzed, 10% were biparasitized and 6% had more than two parasitic species. The most frequently detected parasites were Blastocystis spp., Giardia intestinalis and Ascaris lumbricoides. The educational intervention was positive, resulting in an improvement in the level of knowledge related to intestinal parasitosis and its prevention. This educational intervention experience highlights the importance of ongoing education in promoting a healthy lifestyle and preventing parasitosis in vulnerable populations.

Strongyloides stercoralis infection: an underlying cause of invasive bacterial infections of enteric origin. Results from a prospective cross-sectional study of a northern Italian tertiary hospital.

PURPOSE OF THE STUDY: We assessed the prevalence of S. stercoralis in a cohort of inpatients with invasive bacterial infections of enteric origin to investigate whether the parasite may facilitate these bacterial infections even in the absence of larval hyperproliferation. METHODS: We performed a prospective cross-sectional study in a hospital in northern Italy. Subjects admitted due to invasive bacterial infection of enteric origin and potential previous exposure to S. stercoralis were systematically enrolled over a period of 10 months. S. stercoralis infection was investigated with an in-house PCR on a single stool sample and with at least one serological method (in-house IFAT and/or ELISA Bordier). Univariate, bi-variate and logistic regression analyses were performed. RESULTS: Strongyloidiasis was diagnosed in 14/57 patients (24.6%; 95% confidence interval 14.1-37.8%) of which 10 were Italians (10/49, 20.4%) and 4 were migrants (4/8, 50.0%). Stool PCR was performed in 43/57 patients (75.4%) and no positive results were obtained. Strongyloidiasis was found to be significantly associated (p ≤ 0.05) with male gender, long international travels to areas at higher endemicity, deep extra-intestinal infectious localization and solid tumors. In the logistic regression model, increased risk remained for the variables deep extra-intestinal infectious localization and oncologic malignancy. CONCLUSIONS: Our findings suggest a new role of chronic strongyloidiasis in favoring invasive bacterial infections of enteric origin even in the absence of evident larval dissemination outside the intestinal lumen. Further well-designed studies should be conducted to confirm our results, and possibly establish the underlying mechanisms.

Salt-Tolerant Plants as Sources of Antiparasitic Agents for Human Use: A Comprehensive Review.

Parasitic diseases, especially those caused by protozoans and helminths, such as malaria, trypanosomiasis, leishmaniasis, Chagas disease, schistosomiasis, onchocerciasis, and lymphatic filariasis, are the cause of millions of morbidities and deaths every year, mainly in tropical regions. Nature has always provided valuable antiparasitic agents, and efforts targeting the identification of antiparasitic drugs from plants have mainly focused on glycophytes. However, salt-tolerant plants (halophytes) have lately attracted the interest of the scientific community due to their medicinal assets, which include antiparasitic properties. This review paper gathers the most relevant information on antiparasitic properties of halophyte plants, targeting human uses. It includes an introduction section containing a summary of some of the most pertinent characteristics of halophytes, followed by information regarding the ethnomedicinal uses of several species towards human parasitic diseases. Then, information is provided related to the antiprotozoal and anthelmintic properties of halophytes, determined by in vitro and in vivo methods, and with the bioactive metabolites that may be related to such properties. Finally, a conclusion section is presented, addressing perspectives for the sustainable exploitation of selected species.

Levamisole hydrochloride as an anthelmintic against Neoechinorhynchus buttnerae in juvenile Colossoma macropomum.

Acanthocephalosis is caused by the endoparasite Neoechynorhyncus buttnerae and affects fish farmed in the Amazon. This study assessed the efficacy of therapeutic levamisole hydrochloride (LVC) baths against N. buttnerae and its effects on juvenile tambaqui blood parameters. In vitro and in vivo tests were carried out, the latter employing two experimental therapeutic LVC bath protocols. Concerning in vitro efficacy, the T75 (75 mg.L-1 LVC) and T100 (mg.L-1 LVC) treatments were 100% effective in 15 min, while the T50 (50 mg.L-1 LVC) and T25 (25 mg.L-1 LVC) treatments required parasite exposure for 45 and 60 min, respectively. During exposure, the parasites displayed reduced motility, proboscis retraction, coiling into a spiral shape, body rigidity and swelling. The LVC LC50-72h for juvenile tambaqui was 115 mg.L-1 . Regarding in vivo efficacy for Protocol I (8-h bath), the T125 resulted in 82% effectiveness, while in Protocol II (two 8-h baths with a 24-h interval), the T115 treatment (115 mg.L-1 LVC) achieved 95.6% effectiveness without clinical intoxication signs, despite behavioural changes. No significant changes were observed in fish blood parameters. LVC was, therefore, highly effective both in vitro and in vivo in controlling the acanthocephalan N. buttnerae without compromising tambaqui juvenile homeostasis.

Pharmacological Interventions for Primary Psychodermatologic Disorders: An Evidence Mapping and Appraisal of Randomized Controlled Trials.

BACKGROUND: The lack of clinical guidelines for the treatment of primary psychodermatologic disorders (PPDs) hinders the delivery of optimal care to patients. The review aimed to identify, appraise, and summarize the currently available evidence about the safety and effectiveness of pharmacological management of PPDs through randomized controlled trials (RCTs). METHODS: The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRIMSA) statement and the Global Evidence Mapping Initiative guidance were followed. Medline, Embase, PsycInfo, Cochrane and Scopus were searched, and two reviewers independently completed article review, data extraction, and quality assessment. RESULTS: Among 2618 unique studies, full texts of 83 were reviewed and 21 RCTs were included. Five PDDs were identified: trichotillomania (n = 12), pathologic skin picking (n = 5), nail biting (n = 2), delusional parasitosis (n = 1), and dermatitis from compulsive hand washing (n = 1). Seven different classes of medications were investigated: SSRIs (i.e., fluoxetine, sertraline, and citalopram), tricyclic antidepressants (i.e., clomipramine and desipramine), antipsychotics (i.e., olanzapine and pimozide), anticonvulsant (i.e., lamotrigine), N-acetylcysteine, inositol, and milk thistle. RCT-derived evidence supports the use of antidepressants in trichotillomania (sertraline and clomipramine), pathologic skin picking (fluoxetine), pathologic nail biting and dermatitis from compulsive hand washing (clomipramine or desipramine); antipsychotics in trichotillomania (olanzapine) and delusional parasitosis (pimozide); N-acetyl cysteine in trichotillomania and skin picking. CONCLUSION: Few pharmacotherapies for primary psychodermatologic disorders are assessed through controlled trials in the literature. This review serves as a roadmap for researchers and clinicians to reach informed decisions with current evidence, and to build on it to establish guidelines in the future.

Statin and aspirin use in parasitic infections as a potential therapeutic strategy: A narrative review.

Infections, including zoonoses, constitute a threat to human health due to the spread of resistant pathogens. These diseases generate an inflammatory response controlled by a resolving mechanism involving specialized membrane lipid-derived molecules called lipoxins, resolvins, maresins, and protectins. The production of some of these molecules can be triggered by aspirin or statins. Thus, it is proposed that modulation of the host response could be a useful therapeutic strategy, contributing to the management of resistance to antiparasitic agents or preventing drift to chronic, host-damaging courses. Therefore, the present work presents the state of the art on the use of statins or aspirin for the experimental management of parasitic infections such as Chagas disease, leishmaniasis, toxoplasmosis or malaria. The methodology used was a narrative review covering original articles from the last seven years, 38 of which met the inclusion criteria. Based on the publications consulted, modulation of the resolution of inflammation using statins may be feasible as an adjuvant in the therapy of parasitic diseases. However, there was no strong experimental evidence on the use of aspirin; therefore, further studies are needed to evaluate its role inflammation resolution process in infectious diseases.

Oral manifestations of delusional infestation: a case series.

BACKGROUND: Delusional infestation (DI) is a rare psychotic disorder characterized by a patient's false belief that the body is infested with living or non-living organisms in the absence of clinical evidence of disease. Based on the underlying etiology, DI can be classified into primary and secondary forms based on the presence or absence of an underlying condition or previously diagnosed psychiatric disorder. This paper discusses a condition that is not commonly reported in the literature. CASE PRESENTATION: Here, we describe four patients diagnosed with DI of the oral cavity. In each case, the patients' intraoral examinations revealed either traumatic lesions or no signs of mucosal disease. Management involved symptom management, medical therapy, and/or a referral to the primary care provider. CONCLUSION: Because oral health care providers may encounter patients with DI, they should familiarize themselves with this unusual condition in order to recognize the condition and initiate prompt referral to a psychiatrist.

Association of urogenital and intestinal parasitic infections with type 2 diabetes individuals: a comparative study.

BACKGROUND: Globally, urogenital and intestinal parasitosis remain significant health challenges. They are associated with rising morbidity, death, and many harmful outcomes. A little is known concerning parasitosis and type 2 diabetes mellitus. Our study planned to investigate the urogenital and intestinal parasitic infections among type 2 diabetes patients compare to non-diabetic (Control) individuals and examine the intensity of helminthiasis in both groups. METHODS: At Kosti Teaching Hospital (Sudan), 300 Urine and 300 stool samples have collected from 150 type 2 diabetes and 150 control individuals, along with the socio-demographic data using a structured questionnaire. The parasitic infections were examined by direct sedimentation technique for urine specimens. Whereas, for fecal samples, simple-direct saline, formal-ether concentration, Kato-Katz, and modified Ziehl-Neelsen techniques were used. RESULTS: Out of 150 type 2 diabetes patients studied, 31 (20.6%) and 14 (9.3%) had intestinal parasitosis and urogenital schistosomiasis, respectively. Whereas, 16 (10.6%) and 8 (5.3%) of the control group were infected, respectively. Compared to the control group, the odds of testing positive for either urogenital schistosomiasis (AOR: 2.548, 95% CI: 0.836-7.761, P = 0.100) or intestinal parasitic diseases (AOR: 2.099, 95% CI: 0.973-4.531, P = 0.059) were greater in diabetic individuals. Likewise, the intensities of helminthiasis were much higher in the diabetic patients and positively correlated with the duration of illness. The rate of urogenital schistosomiasis was also significantly different among the disease duration subcategories. CONCLUSIONS: Our study has highlighted the relationship of type 2 diabetes with urogenital and intestinal parasitic infections and enhanced our knowledge about the frequency of particular urogenital and intestinal parasites as well as the intensity of helminths infection in type 2 diabetes compared to non-diabetic individuals, which are important for further studies.

Case report: an unusual unilateral pterygium - a secondary pterygium caused by parasitosis in the scleral fistula.

BACKGROUND: Ocular parasitosis can cause eye damage, which contribute to eye symptoms such as burning, itching and even blindness. It is uncommon to see the parasitosis lying in the sclera layer, neither it causing pterygium. Here, we present an unusual case of a secondary pterygium caused by intrascleral worm. CASE PRESENTATION: A 52-year-old women complained about discomfort in right eye for 6 years. Slit-lamp examination indicated a thickened triangular layers of conjunctiva extending from the nasal edge to the cornea. The diagnosis was pterygium in the right eye. To our surprise, after scleral of nasal side exposed, we could see a tiny fistula right in the sclera which lied right under the pterygium, with an alive and motile worm inside. An intrascleral fistula was noted. Then the worm was removed by forceps from the fistula, which was creamy white, thread-like and 1 cm long. DISCUSSION AND CONCLUSIONS: As far as we known, it is the first case of an intrascleral worm hidden beneath the conjunctiva which caused the secondary pterygium. It is hard to know the etiology of the secondary pterygium which caused by parasitosis in the scleral fistula untill excision surgery. It is hard to imagine the worm was living in the sclera of the patient for a long-time.

Parasitosis of the vertebral canal mimicking lumbar intervertebral disc herniation: a case report.

STUDY DESIGN: Case report. BACKGROUND: It is a case of dracunculiasis of the spine mimicking lumbar intervertebral disc herniation. CASE PRESENTATION: A 57 year-old Caucasian male was admitted to the hospital because of the left L5 radiculopathy lasting for 2 months. The pain in the left lower limb was associated with muscle weakness on dorsal flexion of the foot, paresthesia of the dorsal aspect of the foot and tingling in the big toe. Neurological examination revealed: muscle weakness on dorsal flexion of the foot, impaired light touch and pin prick test on the dorsal aspect of the foot and positive Lasègue's sign. Magnetic resonance imaging (MRI) examination revealed L4-L5 intervertebral disc herniation with sequester compressing the left L5 nerve root. The open L4-L5 left side discectomy was performed. During the sequester evacuation 3 pieces of nematodes were removed and preserved in 10% of formaldehyde solution. After the surgery the patient was pain free with normal neurological examination. The diagnosis of dracunculiasis was based on the morphology of the nematode and on exclusion of the other parasites. DM infestation could not be confirmed with molecular testing that was impaired by the formaldehyde. CONCLUSIONS: Parasite infestation should be considered even in cases with obvious MRI of lumbar intervertebral disc herniation. If a nematode was found accidentally during any surgery it should be preserved in a 0.9% saline, not in formaldehyde, not to disturb the molecular tests.

[Parasitoses in childhood]. / Parasitosen im Kindesalter.

Parasitoses are a frequent occurrence in pediatric consultations in both hospitals and private practices. Responsible for this are parasites that permanently infest human skin, such as Sarcoptes scabiei hominis and Pediculus humanus capitis (persistent parasites) as well as those that only attack the skin for feeding, such as Pulex irritans, Cimex lectularius und Neotrombicula autumnalis (transient parasites). The main symptom of parasitoses is pruritus, which is caused by a delayed allergic reaction to proteins in the saliva of the parasites. In some parasitoses, such as scabies, the pruritus is typical, occurs particularly at night and is associated with a considerable impairment in the quality of life due to the resulting lack of sleep, whereas the pruritus is often absent in the case of pediculosis capitis. In this article persistent and transient parasitoses are characterized based on the patient history, morphology and symptoms.

Delusional infestation in clinical practice over a period of two decades.

INTRODUCTION: Patients presenting with cutaneous symptomatology may in fact suffer from underlying psychiatric conditions. Individuals diagnosed with delusional infestation (DI) have a fixed false belief of being infested with certain organisms or objects. AIM: To analyse clinical features of subjects with DI who were admitted to the tertiary dermatology ward. MATERIAL AND METHODS: A retrospective analysis concerning DI patients hospitalized between 1997 and 2019 was carried out. The emphasis was put on the duration of symptoms, psychiatric symptomatology (including the "specimen sign"), comorbidities as well as therapy. RESULTS: We gathered data regarding 21 consecutive patients with DI. The mean age of subjects was 65.2 ±13.3 years, the majority were females (76.2%). The mean time span between the disease onset and diagnosis was 1.9 ±1.7 years. Previous psychiatric consultations were attended by 57.0% of patients. The specimen sign was present in 47.6% of cases, whereas the most common suspected causative factors were described as worms (52.4%), unspecified parasites (42.9%), "something" (33.3%) and flies (19.0%). Primary delusional disorder was diagnosed in 76.2%, followed by shared delusional disorder and secondary delusional disorder of organic origin (9.5% each). Risperidone monotherapy was initiated in 61.9% of patients. In total, only 33.3% of patients attended the follow-up visit. CONCLUSIONS: DI features a wide spectrum of clinical signs and symptoms. Risperidone remains the drug of choice in the majority of cases. Successful management of each DI case requires collaboration between dermatologists and psychiatrists and still remains a major challenge.

Historical and clinical considerations on Ekbom's syndrome.

Ekbom's syndrome represents a relatively uncommon neuropsychiatric condition characterized by the recurrent and bizarre fixed delusional belief to be infested by small organisms or even unanimated materials ('Morgellons disease'), without any objective evidence of infestation/parasitosis. The condition, mainly diagnosed in a nonpsychiatric setting, is supposed to be largely underestimated and, hence, undermanaged. The present comprehensive review aims at investigating Ekbom's syndrome, from a historical, epidemiological, clinical and therapeutic perspective, by providing diagnostic-treatment strategies in managing this condition in routine psychiatric clinical settings. The prototypical patient is a middle-aged woman (or a younger subject in those cases in which substance and/or alcohol abuse is implicated), often single, divorced or widowed (loneliness component and social withdrawal), who has already consulted several specialists due to skin lesions associated with a firm and delusional belief to be infested. The identification and diagnosis are challenging due to poor patient's insight, poor knowledge and collaboration between specialists and differential diagnoses to be considered before asking for a psychiatric referral. Management and treatment strategies mainly derive from isolated case reports or observational studies with a small sample size. Further randomized clinical trials should be performed to evaluate the efficacy of newer antipsychotic drugs, including long-acting injectable formulations.

Cranial crassicaudiasis in two coastal dolphin species from South Africa is predominantly a disease of immature individuals.

Crassicauda spp. (Nematoda) infest the cranial sinuses of several odontocetes, causing diagnostic trabecular osteolytic lesions. We examined skulls of 77 Indian Ocean humpback dolphins Sousa plumbea and 69 Indo-Pacific bottlenose dolphins Tursiops aduncus, caught in bather-protecting nets off KwaZulu-Natal (KZN) from 1970-2017, and skulls of 6 S. plumbea stranded along the southern Cape coast in South Africa from 1963-2002. Prevalence of cranial crassicaudiasis was evaluated according to sex and cranial maturity. Overall, prevalence in S. plumbea and T. aduncus taken off KZN was 13 and 31.9%, respectively. Parasitosis variably affected 1 or more cranial bones (frontal, pterygoid, maxillary and sphenoid). No significant difference was found by gender for either species, allowing sexes to be pooled. However, there was a significant difference in lesion prevalence by age, with immature T. aduncus 4.6 times more likely affected than adults, while for S. plumbea, the difference was 6.5-fold. As severe osteolytic lesions are unlikely to heal without trace, we propose that infection is more likely to have a fatal outcome for immature dolphins, possibly because of incomplete bone development, lower immune competence in clearing parasites or an over-exuberant inflammatory response in concert with parasitic enzymatic erosion. Cranial osteolysis was not observed in mature males (18 S. plumbea, 21 T. aduncus), suggesting potential cohort-linked immune-mediated resistance to infestation. Crassicauda spp. may play a role in the natural mortality of S. plumbea and T. aduncus, but the pathogenesis and population level impact remain unknown.