Proptosis in early childhood can be an alarming and stressful situation for parents and paediatricians. Different types of anatomical structures can be found in the orbit, such as nerves, muscles, veins, arteries, glandular and connective tissue and hence the differential diagnosis of unilateral proptosis can be vast. In some cases, orbital disease has the potential to cause substantial morbidity and mortality. Appropriate medical history, examination and diagnostic evaluation with imaging can assist with a prompt diagnosis and management. In young infants, a heightened level of suspicion should be maintained since orbital haemangiomas are the most prevalent primary lesions of the orbit presenting with proptosis. We report the case of an infant who presented at 3 months of age to our Emergency Department with a 2-week history of noticeable and progressively worsening right-sided proptosis.

Thyrotoxic hypokalemic paralysis is a rare complication of hyperthyroidism, characterized by acute, reversible episodes of muscle weakness associated with severe hypokalemia, secondary to intracellular potassium redistribution mediated by excess thyroid hormones and activation of the Na+/K+ - ATPase pump. Its incidence is approximately 0.2% and it occurs predominantly in males. In this report, we describe four cases of hypokalemic paralysis associated with thyrotoxicosis. All patients were male, aged between 21 and 37 years. The predominant clinical presentation was acute-onset muscle weakness, mainly proximal, with greater involvement of the lower limbs. In three of the four cases, paralysis was the main initial manifestation of hyperthyroidism due to Graves' disease. Potassium replacement combined with antithyroid therapy and beta-blockers resulted in complete resolution of the muscle weakness and adequate disease control in all patients. Therefore, thyrotoxic hypokalemic paralysis should be considered among the differential diagnoses in patients presenting with muscle weakness, as well as among the complications associated with hyperthyroidism.

A 48-year-old man was diagnosed with IgG4-related disease (IgG4-RD) during an evaluation for exophthalmos and unexplained pain on the left side of his face. The diagnosis was made by ruling out all other possible conditions and was based on histopathological findings. After initiating immunosuppressive therapy with corticosteroids (GC), most of the symptoms resolved. As the GC-dose was gradually reduced, a relapse occurred, leading to two courses of Rituximab. Reflecting the success of the therapy, long-term follow-up revealed a marked radiological reduction in the retrobulbar mass and a significant clinical improvement in pain.

A 5-year-old cat presented with exophthalmos and neurological signs. Aspergillus udagawae was identified by histopathological examination and polymerase chain reaction (PCR) analysis of an orbital mass. Although magnetic resonance imaging suggested intracranial infection, cerebrospinal fluid (CSF) analysis and fungal culture were not clear. Serial CSF PCR detected Aspergillus sp., leading to diagnosis of central nervous system (CNS) infection and monitoring of treatment response. Following surgical debulking and administration of antifungal agents including voriconazole, the clinical signs resolved and CSF PCR reverted to negative. This case suggests that CSF PCR is a sensitive adjunctive tool for diagnosing and monitoring CNS aspergillosis in cats when conventional methods are inconclusive.

Congenital malformations (CMFs) are structural disorders that arise during embryogenesis, and various forms of these abnormalities have been reported in reptiles. The yacare caiman (Caiman yacare) is widely used in commercial farms in the Pantanal region, and studies characterizing CMFs in these animals are scarce. This study describes the pathological and imaging findings of CMFs in farmed caimans. From February 2022 to February 2023, the incubation and maternity of a caiman commercial farm, operating in ranching and farming systems, were monitored. A total of 26 distinct CMFs were identified in 30 farmed caimans. All animals were classified as infantile (9.65 ± 2.69 cm snout-vent length). CMFs were grouped according to anatomical site, with craniofacial disorders (18 cases) being the most frequent findings, followed by spinal malformations (13 cases). Palatoschisis (PC) and cheiloschisis (CL) were reported in 6 yacare caimans, which also exhibited a malformed palatal velum and secondary aspiration pneumonia. Meningoencephalocele was diagnosed in 3 caimans, with brain hemorrhage being a typical secondary lesion in these cases. Anophthalmus, exophthalmos, and cyclopia represented the ocular CMFs. Spinal malformations (kyphosis and scoliosis) were detected in 13 yacare caimans and were thoroughly characterized by the X-ray radiographic analysis. Tail abnormalities were reported in 12 animals, including tail agenesia (1 case) and coiled tail (11 cases). Other sites of CMFs include the limbs, the coelomic wall, and the skin. Radiographic assessments were obtained from all 30 CMFs, providing detailed information on these lesions.

Alpha-mannosidosis is a rare lysosomal storage disease caused by a deficiency of the enzyme alpha-mannosidase. It manifests as a continuous spectrum of signs and symptoms characterized by dysmorphic features, skeletal abnormalities, delayed psychomotor and speech development, impaired hearing, and psychiatric involvement. When suspected, alpha-mannosidosis must be confirmed by biochemical and molecular testing, namely, assessment of blood levels of alpha-mannosidase in leukocytes or fibroblasts and Sanger or next-generation sequencing of the MAN2B1 gene. The disease must be diagnosed and treatment started as quickly as possible, since the long-term prognosis for untreated patients is very poor. Enzyme replacement therapy (ERT, human recombinant alpha-mannosidase) has replaced allogeneic stem cell transplant as the mainstay of therapy, thus improving disease-related outcomes with, for example, reduced serum oligosaccharide levels, greater functional capacity, and improved quality of life, all with a good safety profile. We report the seventh case of alpha-mannosidosis in Spain. The patient was a 3.5-year-old girl assessed in the clinical genetics department for developmental delay and marked dysmorphic features (trigonocephaly, exophthalmos, hypertelorism, and a flat nasal bridge). Radiography revealed shortening and thickening of the long bones, as well as metopic and coronal synostosis. Craniosynostosis was treated with surgery. Assessment of alpha-mannosidase revealed complete absence of enzymatic activity. Genetic analysis revealed the homozygous pathogenic variant of MAN2B1, c.2248C>T, which is associated with alpha-mannosidosis. ERT is the only currently available pharmacological option for treating children with mild-to-moderate alpha-mannosidosis. Without ERT, patients' quality of life would be impaired, and their prognosis would worsen significantly.