Detection of cytomegalovirus DNA in preserved umbilical cords from patients with sensorineural hearing loss.

We performed a retrospective diagnostic study of congenital cytomegalovirus (CMV) infection in patients with sensorineural hearing loss (SNHL). CMV DNA in preserved umbilical cords was analyzed using real-time polymerase chain reaction analysis. Of 45 analyzable patients with SNHL, CMV DNA was detected in the preserved umbilical cords of 3 patients, all of whom had bilateral SNHL that lacked a clear onset period. CMV DNA was not detected in any of the patients with sudden SNHL or enlarged vestibular aqueduct-associated SNHL. The features of CMV-associated SNHL were more asymmetric than those of CMV-negative bilateral SNHL.

Viral etiology for inner ear diseases: proven, unproven, unlikely.

This is a revision article that deals with the broad field of inner ear disease caused by viral infections. Some of these entities have been proven to have a viral etiology. Others have strong evidence in favor of a viral causation but still cannot be considered as a viral disease. Finally, other entities are suggestive of a viral etiology but when the whole body of evidence is considered one concludes that a viral etiology is indeed unlikely. We review the literature and add our own experience in this subject. Clearly, the most important evidence about this subject came from the study of temporal bone histopathology. Certainly, we can learn much more if we continue to collect and study temporal bone specimens histopathologically.

Otosclerosis and measles virus - association or causation?

Otosclerosis is a frequent condition which occurs exclusively in the human temporal bone. This peculiar disease affects mainly Caucasians and Indians and may cause conductive, mixed conductive-sensorineural or occasionally merely sensorineural hearing loss. Morphological investigations of the otosclerotic focus show all three phases of a chronic inflammation with bone resorption, formation of new bone and finally eburnation. Various hypotheses about the cause of inflammation were proposed in the past. Immunological reactivity to collagen, the existence of otosclerosis genes (OTSC 1-5) including mutations of the collagen gene 1A1 and 1A2 or a measles virus (MV) infection were suggested. The existence of the MV proteins and RNA within the otosclerotic tissue has been shown by several authors. However, due to mainly technical problems, no further progress to elucidate the role of the virus could be made. Epidemiological studies revealed a dramatic decrease of measles and related diseases such as the subacute sclerosing panencephalitis since the introduction of MV vaccination programs in USA and Europe. Indeed, some surgeons reported decreasing numbers of stapes surgery and a shift towards elder patients. Our epidemiological survey of all patients hospitalized with otosclerosis in Germany between 1993 and 2004 demonstrates a highly significant decrease in otosclerosis among the population vaccinated against the MV. The strong correlation makes it most plausible that the MV is at least one triggering factor for the development of otosclerosis.

Measles virus prevalence in otosclerotic foci.

The etiology of otosclerosis is still unknown. Persistent measles virus infection of the otic capsule is supposed to be one of the etiologic factors in otosclerosis. The presence of measles virus was shown in otosclerotic patients by RT-PCR amplification of the viral RNA, detecting the viral proteins by immunohistochemistry and antimeasles immunoglobulin G in the perilymph samples. Nucleic acid (mRNA, vRNA, DNA) was extracted from pulverized, frozen stapes footplate samples of otosclerotic patients. Measles virus RNA was amplified by RT-PCR: reverse transcription and the first-round PCR amplification were performed by heat-stable recombinant Thermus thermophilus polymerase, while in the nested round PCR Taq polymerase was employed. Oligonucleotide primers specific to measles virus nucleoprotein and matrix protein RNA were used in these reactions. Edmonston- and Schwartze-type measles viruses served as positive controls and cortical bone fragments, stapes superstructures, cadaver stapes, incus and malleolar samples served as negative controls. Among 102 otosclerotic patients, 62 stapes footplate samples contained measles virus RNA. Measles virus RNA was not detected in other bone specimens of the patients. The etiologic role of measles virus in the pathogenesis of otosclerosis should be considered. The 40 negative samples may be genetically determined otosclerotic cases or stapes fixations due to other causes.

Detection of human papillomavirus in temporal bone inverted papilloma by polymerase chain reaction.

There is debate about the role of human papillomavirus in the induction of rare inverted papillomas involving the temporal bone and in the higher recurrence rates and association with squamous cell carcinoma of temporal bone inverted papillomas compared with sinonasal inverted papillomas. An exhaustive review of the literature revealed that eight cases of temporal bone inverted papilloma have been analysed for human papillomavirus. None of the cases studied with in situ hybridization proved positive. Only one case was found to be positive using the more sensitive polymerase chain reaction assay. We present the first two cases of Schneiderian-type papilloma involving the temporal bone to be analysed by type-specific polymerase chain reaction methods for human papillomavirus.

The pathology of the temporal bones of a child with acquired cytomegalovirus infection: studies by light microscopy, immunohistochemistry and polymerase-chain reaction.

STUDY DESIGN: The first case of an acquired cytomegalovirus (CMV) infection of the inner ear is reported in a 3-year-old girl in remission from acute lymphocytic leukemia. METHODS: Horizontal sections of the temporal bones were studied by light microscopy and immunohistological staining by avidin-biotin-complex-technique was performed on selected archival sections. Three sections were processed for detection of the virus genome by the polymerase chain reaction (PCR). RESULTS: By light microscopy the epithelium of the endolymphatic sac, the utricle and the semicircular canals showed deeply stained acidophilic inclusions and the stria vascularis had a loose structure especially in the intermediate layer. The changes were limited to the non-sensory parts of the labyrinth and no CMV type cells were observed in the organ of Corti. There was a loss of inner and outer hair cells and loss of cochlear ganglion cells caused by either the virus or treatment with gentamicin. Standard immunohistochemistry failed to demonstrate staining with CMV antibodies, but PCR, demonstrated CMV-DNA in one section. CONCLUSION: Molecular techniques may be able to detect acquired CMV infections in archival pediatric bones temporal bones. The histologic findings in the labyrinth were milder, however showed some similarity to children with congenital CMV labyrinthitis.

Amplification of herpes simplex virus type 1 DNA in human geniculate ganglia from formalin-fixed, nonembedded temporal bones.

Polymerase chain reaction (PCR) has provided new insights in molecular biology. Recently, some studies have been focused on temporal bone pathology, with amplification of DNA from fixed sections of celloidin-embedded bones. The purpose of our study was to elucidate the utility of PCR in detection of minor concentrations of DNA from nonoptimal stored samples. We obtained geniculate ganglia from 30 temporal bones preserved in formalin for a long time, without any process of embedding. By performing a nested PCR assay, we detected herpes simplex virus type 1 DNA in 13 of 30 ganglia (43%). We conclude therefore that study of temporal bones stored under poor conditions by PCR is possible, although there are some limitations when compared with fresh or optimally archived samples.

Highly variable distribution of HSV-1-specific DNA in human geniculate, vestibular and spiral ganglia.

Viral reactivation in temporal ganglia is the suspected cause of Bell's palsy, vestibular neuritis and sudden hearing loss. Since the distribution of latent herpes simplex type 1 (HSV-1) in geniculate, vestibular and spiral ganglia of individual human temporal bones could have implications for the explanation of isolated as well as combined disorders of these three cranial nerves, we examined these ganglia in 18 human temporal bones of adults by nested polymerase chain reaction. In all of the temporal bones HSV-1 specific DNA was detected: 10/18 (56%) of the geniculate, 11/18 (61%) of the vestibular and 9/18 (50%) of the spiral ganglia samples were positive. All combinations of positive and negative ganglia were found in individual temporal bones at roughly equal frequencies. These data support a viral etiology of all three conditions, especially their occasional combinations.

Molecular temporal bone pathology: II. Ramsay Hunt syndrome (herpes zoster oticus).

In 1907 J. Ramsay Hunt suggested that herpes zoster oticus resulted from a geniculate ganglionitis; however, many contemporary authors believe that this disorder represents a neuritis or polycranial neuropathy. Herpes varicella-zoster viral (VZV) DNA was identified, using the polymerase chain reaction, in archival celloidin-embedded temporal bone sections from two patients who clinically had Ramsay Hunt syndrome (herpes zoster oticus). The presence of VZV was confirmed by sequencing the PCR products. These experiments demonstrated that VZV genomic DNA was present in the geniculate ganglion of the side with facial paralysis and cutaneous recrudescence in both patients and in the clinically unaffected side in patient 1. In addition, patient 2 had a sudden hearing loss and was found to have VZV genomic DNA in sections from the affected side containing the spiral ganglion, Scarpa's ganglion, organ of Corti, and macula of the saccule. No VZV genomic DNA was identified in temporal bone sections from five patients with Bell's palsy and ten patients without evidence of otologic disease. In this study, the histopathology of these two cases yielded complementary information regarding the role of VZV in herpes zoster oticus. These data suggest that in patients with Ramsay Hunt syndrome, latent VZV is located in the geniculate ganglia and may be present in the auditory and vestibular primary afferent ganglia in some patients.

Polymerase chain reaction amplification of a measles virus sequence from human temporal bone sections with active otosclerosis.

Investigation of a possible viral etiology for otosclerosis was initiated because of the clinical and histopathologic similarities between otosclerosis and Paget's disease of bone and the mounting evidence of a viral etiology in Paget's disease. Thus far, ultrastructural and immunohistochemical studies have revealed measles-like structures and antigens in active otosclerotic lesions. A method for isolation and identification of both DNA and RNA sequences in archival human temporal bone specimens using the polymerase chain reaction technique has been developed. With use of this technique, a 115-base pair sequence of the measles nucleocapsid gene has been identified in 8 of 11 different temporal bone specimens with histologic evidence of otosclerosis. Zero of nine control specimens without histologic evidence of otosclerosis were positive. The association between the presence of the measles nucleocapsid gene sequence and histologic otosclerosis was significant (p < 0.01). This study provides further evidence for a possible measles virus etiology in otosclerosis.

Polymerase chain reaction amplification of herpes simplex viral DNA from the geniculate ganglion of a patient with Bell's palsy.

Bell's palsy is the most common cause of facial paralysis. In this study, we demonstrate the presence of herpes simplex viral type 1 (HSV-1) genomic DNA in the geniculate ganglion of a patient who had Bell's palsy. This association suggests that in this patient, HSV-1 may have caused Bell's palsy. If HSV-1 is a cause of Bell's palsy, treatment with acyclovir may be beneficial. Additional studies should be done to establish the prevalence of HSV-1 as an etiologic agent of Bell's palsy.