Hyperglycemic acidotic coma and death in Kearns-Sayre syndrome

Overlap between ophthalmology and psychiatry - A narrative review focused on congenital and inherited conditions

A number of congenital and inherited diseases present with both ocular and psychiatric features. The genetic inheritance and phenotypic variants play a key role in disease severity. Early recognition of the signs and symptoms of those disorders is critical to earlier intervention and improved prognosis. Typically, the associations between these two medical subspecialties of ophthalmology and psychiatry are poorly understood by most practitioners so we hope to provide a narrative review to improve the identification and management of these disorders. We conducted a comprehensive review of the literature detailing the diseases with ophthalmic and psychiatric overlap that were more widely represented in the literature. Herein, we describe the clinical features, pathophysiology, molecular biology, diagnostic tests, and the most recent approaches for the treatment of these diseases. Recent studies have combined technologies for ocular and brain imaging such as optical coherence tomography (OCT) and functional imaging with genetic testing to identify the genetic basis for eye-brain connections. Additional work is needed to further explore these potential biomarkers. Overall, accurate, efficient, widely distributed and non-invasive tests that can help with early recognition of these diseases will improve the management of these patients using a multidisciplinary approach.

Kearns-Sayre Syndrome: A Case Report and Review

In 1958, Kearns and Sayre described a multisystem entity, now known as Kearns-Sayre syndrome (KSS). The syndrome is defined as exhibiting a triad of thus far unexplained degenerative conditions: progressive external ophthalmoplegia, retinal pigmentary degeneration, and heart block. Commonly accompanying findings include cerebellar dysfunction and CSF protein levels above 100 mg/dl. Symptoms usually appear in early childhood, but the onset has been seen occasionally in young adults. KSS is a mitochondrial disorder that occurs rarely; the actual incidence is unknown. Ocular findings consist of bilateral ptosis, chronic progressive external ophthalmoplegia, and pigmentary retinopathy. Corneal clouding and optic neuritis are infrequent.

We herein report a classic case of Kearns Sayre syndrome and discuss the findings.

Mitochondrial A3243G mutation results in corneal endothelial polymegathism

PURPOSE

The mitochondrial DNA point mutation A3243G leads to a spectrum of syndromes ranging from MIDD to MELAS. Ocular manifestations include pattern macular dystrophy and concentric perifoveal atrophy. Given the high metabolic demand of corneal endothelial cells, we performed specular biomicroscopy analysis in patients harboring the mitochondrial DNA point mutation A3243G to assess for the associated presence of corneal endothelial abnormalities.

METHODS

We present a case series with participants from two institutions. Patients diagnosed with macular dystrophy associated with MIDD or MELAS, and the mitochondrial DNA point mutation A3243G were recruited. Exclusion criteria included a prior diagnosis, or a positive family history, of endothelial corneal dystrophy. Slit-lamp corneal examination and specular biomicroscopy were performed. Corneal endothelial cell count, cell size and polymegathism, and central corneal thickness were assessed. Patients diagnosed with MIDD or MELAS based on clinical history and examination were genetically tested for the mitochondrial DNA point mutation A3243G using pyrosequencing.

RESULTS

Five patients (two male and three female participants) from five different families, and with different ethnic backgrounds, met the inclusion criteria. Their ages ranged from 41 to 60 years. Corneal endothelial changes observed using slit-lamp examination were primarily mild to rare guttata. Specular biomicroscopy displayed mainly polymegathism associated with guttata. The average endothelial cell count was 2358 ± 456 cells per mm², the average endothelial cell size was 442 ± 103 μm² and the average central corneal thickness (CCT) was 551 ± 33 μm. These values were similar to that of the average population. The average coefficient of variation (COV), an index of heterogeneity in cell size, was 42.0 ± 4.1%. When compared to the average population, the average COV was significantly higher than predicted for the patients' age. None of the patients had signs of corneal edema. One patient had a pre-Descemet's opacity.

CONCLUSIONS

In patients with the mitochondrial DNA point mutation A3243G, corneal endothelial polymegathism is present. This is mainly associated with mild guttata. The findings of corneal endothelial cell polymegathism may be a biomarker of mitochondrial disease, specifically in patients with the mitochondrial DNA A3243G mutation.

Coenzyme Q10 in the Treatment of Corneal Edema in Kearns-Sayre: Is There an Application in Fuchs Endothelial Corneal Dystrophy?

PURPOSE

Corneal involvement in mitochondrial disease is seldom described. Kearns-Sayre syndrome (KSS) is a mitochondrial disorder characterized by retinitis pigmentosa, external ophthalmoplegia, and heart block. We report 2 patients with KSS with corneal lesions involving the endothelium, which improved with Coenzyme Q10 (CoQ10). Based on recent research regarding the role of dysfunctional oxidative metabolism in Fuchs Endothelial Corneal Dystrophy (FECD), we propose that mitochondrial diseases and FECD share a final pathway.

METHODS

A chart review was performed and a review of the literature was completed with a PubMed search using the terms "Kearns-Sayre Syndrome", "mitochondria", "endothelium", "Fuchs endothelial corneal dystrophy", and "cornea".

RESULTS

There are 19 reports of corneal involvement in clinical phenotypes of mitochondrial disease. Nine of these 19 cases had findings consistent with KSS. Our patients with KSS had microcystic changes throughout the cornea and excrescences on the endothelial surface seen with ultrasound biomicroscopy, similar to the clinical findings in FECD. CoQ10 improved corneal disease in both children. CoQ10 deficiency has been reported in a variety of mitochondrial diseases, and efficacy of supplementation has been demonstrated. It may be beneficial in these patients because of its antioxidant properties and role in oxidative phosphorylation.

CONCLUSIONS

The common deletion found in patients with KSS has recently been implicated in FECD, which has recently been shown to be a disease related to dysfunctional oxidative metabolism. Future research should explore the use of antioxidants, such as CoQ10 in patients with FECD.

Respiratory failure in diabetic ketoacidosis

Respiratory failure complicating the course of diabetic ketoacidosis (DKA) is a source of increased morbidity and mortality. Detection of respiratory failure in DKA requires focused clinical monitoring, careful interpretation of arterial blood gases, and investigation for conditions that can affect adversely the respiration. Conditions that compromise respiratory function caused by DKA can be detected at presentation but are usually more prevalent during treatment. These conditions include deficits of potassium, magnesium and phosphate and hydrostatic or non-hydrostatic pulmonary edema. Conditions not caused by DKA that can worsen respiratory function under the added stress of DKA include infections of the respiratory system, pre-existing respiratory or neuromuscular disease and miscellaneous other conditions. Prompt recognition and management of the conditions that can lead to respiratory failure in DKA may prevent respiratory failure and improve mortality from DKA.

Defect of cobalamin intracellular metabolism presenting as diabetic ketoacidosis: a rare manifestation

Hypoglycemia is the usual feature of commonly occurring organic acidemias. Organic acidemias manifesting as hyperglycemia or diabetic ketoacidosis are rare and only a few cases have been reported. We report a 13-month-old boy who presented with vomiting, dehydration, coma, hyperglycemia, high anion gap metabolic acidosis and ketosis, mimicking diabetic ketoacidosis (DKA). Treatment with parenteral fluid, electrolytes, and insulin infusion resulted in an improvement in hyperglycemia, but persistence of metabolic acidosis and lack of improvement of neurologic status led us to suspect an organic acidemia. Urinary organic acid analysis revealed increased methylmalonic acid levels. In addition, hyperhomocysteinemia and homocystinuria were also noted in presence of normal vitamin B12 levels. This confirmed the diagnosis of cobalamin metabolism defect leading to combined methylmalonic aciduria and homocystinuria. There was some improvement in neurologic status and metabolic parameters after treatment with low-protein diet, vitamin B12, folic acid, and L-carnitine, but he ultimately succumbed to polymicrobial nosocomial sepsis. The entire MMACHC gene of the patient was sequenced and no mutations were identified. This is probably the first case report of cobalamin intracellular metabolism defect (CblC/CblD/CblF/CblJ or ABCD4) presenting as diabetic ketoacidosis.

[Oedema with acute pseudokeratoconus corneal aspect in a case of Kearns-Sayre syndrome]

INTRODUCTION

Mitochondrial encephalomyopathy is a set of rare diseases in which corneal involvement is exceptional.

CASE REPORT

A 34-year-old patient, a known carrier of Kearns-Sayre syndrome, was hospitalized for acute corneal decompensation, with a keratoconus-like hydrops stemming from an endothelial-Descemet membrane disruption. Under local hypotonic treatment, the favorable progression was fast with a decline in the edema and coaptation of the endothelial-Descemet membrane disruption.

CONCLUSION

The possible physiopathologic mechanisms are debated; the preferred hypothesis was a dysfunction of endothelial cell pumps. We emphasize the extremely complex medical management of these fragile patients presenting mitochondrial encephalopathy. General corticotherapy is contraindicated and beta-blockers including in eye drops must be used extremely carefully because of cardiac abnormalities such as conduction disturbance and/or arrhythmia and dilated cardiomyopathies.

Hyperglycemic hyperosmolar non-ketotic syndrome in children with type 2 diabetes*

OBJECTIVE

Hyperglycemic hyperosmolar non-ketotic (HHNK) syndrome is thought to be a rare entity in the pediatric population, associated with significant mortality based on case reports in the literature. As obesity and type 2 diabetes in childhood grow in prevalence, such related complications may also increase. This study will serve to provide updated information regarding typical clinical course and sequelae of HHNK syndrome in childhood.

METHODS

Patients diagnosed with type 2 diabetes at Children's Hospital of Philadelphia (CHOP) over a period of 5 yr were screened retrospectively for any laboratory evidence of previous episodes of HHNK syndrome. The standard diagnostic criteria of blood glucose >600 mg/dL and serum osmolality >330 mOsm/L with only mild acidosis (serum bicarbonate >15 mmol/L and small ketonuria 15 mg/dL or less) were utilized.

RESULTS

The records of all patients with type 2 diabetes mellitus (DM) diagnosed over a 5-yr period were reviewed (n=190). Seven patients were found to have one episode of HHNK syndrome by diagnostic criteria (five males, mean age at presentation 13.3 yr, age range 10.1--16.9 yr), yielding a frequency of 3.7%. All were African-American. HHNK syndrome was the clinical presentation at diagnosis of new onset diabetes for all seven children. Three of seven children had a previously diagnosed developmental delay. The average Glasgow Coma Scale (GCS) score at presentation was 13 (range 9--15). Mean body mass index (BMI) at presentation was 32.7 kg/m(2) (n=6). Mean serum osmolality was 393 mOsm/L (n=7), and mean blood glucose was 1604 mg/dL (n = 7). The average time until mental status returned to baseline among survivors was 3 d (range 1--7 d). The average number of hospital days for survivors was 10 (range 5--24 d). Four of seven patients had an uncomplicated course. One patient developed multisystem organ failure and died on hospital day 4. The case fatality rate was 14.3% (one of seven). Survivors had no appreciable neurodevelopmental sequelae.

CONCLUSIONS

This retrospective chart review provides updated information regarding the entity of HHNK syndrome in children. This study supports the need for increased awareness of type 2 diabetes in children so that morbidity and mortality related to HHNK syndrome can be prevented.

An unusual case of the nonketotic hyperglycemic syndrome during childhood

The nonketotic hyperglycemic syndrome is rare during childhood and may occur as the initial manifestation of insulin-dependent diabetes mellitus or during an episode of gastroenteritis. In this article, we report an unusual case of this syndrome in a female infant who had atypically severe hyperglycemia in association with gastroenteritis. In addition, we provide a review of the literature and summarize the pathophysiologic mechanisms of the nonketotic hyperglycemic syndrome.

Endocrine dysfunction in Kearns-Sayre syndrome

Kearns-Sayre syndrome (KSS) is a form of mitochondrial myopathy in which specific clinical features, namely progressive external ophthalmoplegia, pigmentary retinal degeneration and cardiac conduction defects, occur. KSS has also been associated with a variety of endocrine and metabolic disorders, in particular short stature, gonadal failure, diabetes mellitus, thyroid disease, hyperaldosteronism, hypomagnesaemia, and bone, tooth and calcification abnormalities. A case is described exhibiting all of these features. A survey of the literature was conducted to determine the prevalence of these conditions among reported cases. Cases with hypoparathyroidism were considered separately to see if they constituted a distinct subgroup with multiple endocrine dysfunction. Short stature was common, being documented in 38% of cases. Gonadal dysfunction before or after puberty was also common (20% of cases) and affected both sexes equally. Diabetes mellitus was recorded in 13% of cases, half of which required insulin. Thyroid disease, hyperaldosteronism and hypomagnesaemia were uncommon but were probably not looked for in many cases. Bone or tooth abnormalities and calcification of the basal ganglia were found both in those with and without hypoparathyroidism. While endocrine and metabolic dysfunction was found more commonly in those with hypoparathyroidism this is likely to be due to increased recognition rather than increased prevalence. No evidence of an autoimmune polyendocrine syndrome including hypoparathyroidism was found.

Variation in retinal changes and muscle pathology in mitochondriopathies

A variety of retinal changes that have so far not been classified under mitochondriopathies can now be included in this group, since muscle biopsy has identified ragged-red fibers with pathological mitochondriae. The ophthalmological findings in our relatively large group of 12 patients with mitochondrial myopathies are compared with the spectrum of myopathic findings. No obvious correlation exists between the severity of the pathological retinal changes and the characteristic of the myopathic alterations. In addition to fine pigmentation and depigmentation, severe dystrophic changes of the retina, pigment epithelium, and the choroid were observed. In two patients with severe chorioretinal dystrophy the correlation with generalized mitochondriopathy was not suspected prior to muscle biopsy.

Cerebral nuclear magnetic resonance (MRI) in Kearns syndrome

We describe an 11-year-old boy with external ophthalmoplegia, pigment retinopathy, hearing loss, elevated spinal protein and ragged-red fibers on muscle biopsy. Cerebral nuclear magnetic resonance (MRI) demonstrated demyelinating lesions in the white matter of the cerebral hemispheres and the cerebellum. To our knowledge this is the first report on the cerebral MRI findings in Kearns syndrome.