False-negative prenatal diagnosis of restrictive dermopathy

Restrictive dermopathy is a rare autosomal recessive lethal skin dysplasia. It has been assumed that the characteristic morphologic abnormalities should allow a reliable prenatal diagnosis on fetal skin biopsies at about 20 weeks pregnancy. We report on a false-negative prenatal diagnosis.

Restrictive dermopathy in two brothers

BACKGROUND

Restrictive dermopathy is an autosomal recessive phenotype characterized by universal tautness of skin resulting in fetal akinesia and death during the neonatal period. The clinical signs and symptoms of this uncommon disease are described in two brothers, and evidence is provided that fetal biopsy specimens obtained during the 20th week of gestational age are nondiagnostic.

OBSERVATIONS

The first patient was a growth-retarded preterm boy suffering from generalized desquamation, marked joint contractures, and facial hypoplasia. Prominent light microscopic findings were hyperorthokeratosis intermingled with parakeratosis and absence of the elastic fibers in a thinned dermis. Electron microscopic examination of the epidermis revealed a lack of keratin filaments and an abnormal globular shape of the keratohyalin granules. The child died 4 days after birth. A following pregnancy resulted in birth of a preterm boy who died of the same disease within 2 hours. In the 20th week of gestational age, fetal biopsy specimens were obtained, but light and electron microscopy failed to reveal any abnormalities.

CONCLUSIONS

Restrictive dermopathy is a genuine skin disease resulting in fetal akinesia that precludes a normal intrauterine development. The clinical features of this disorder are so distinctive that an on-the-spot diagnosis can be established. In view of the data obtained in this case, the feasibility of prenatal diagnosis should be regarded with great caution.

Experimental autoimmune retinitis in the rat induced by immunization with rhodopsin: an ultrastructural study

Experimental autoimmune retinitis induced by immunization with rhodopsin was investigated in the Lewis rat using transmission electron microscopy and light microscopy. The first signs of retinitis consisted of scattered infiltrations of lymphocytes and other mononuclear cells, predominantly in the inner nuclear layer and outer plexiform layer. Occasionally, some macrophages were detected in the photoreceptor cell layer. Eyes exhibiting a clinically moderate or severe inflammation contained areas of normal retina coexistent with mildly to severely inflamed foci. The central retina was more frequently affected than the peripheral area. In moderately inflamed foci, macrophages infiltrated the photoreceptor cell layer, damaging and eliminating its structures. Inflammatory cells penetrated the photoreceptor outer segment layer which remained unaltered so far in spite of a high serum anti-(rhod)opsin antibody titer. In stages of severe inflammation, massive infiltrations of macrophages and polymorphonuclear cells destroyed the photoreceptor cells focally, leaving the retinal pigment epithelium virtually unaffected. Adjacent to these foci the pigment epithelial cells sometimes exhibited increased numbers of phagosomes and swelling. The locations of the cell infiltrations and lesions in progressive stages of development suggest that the rod outer segments are the target for the autoimmune damage. The described patterns of inflammation were compared with those of previous studies using other animal species and inciting antigens. Especially in rhodopsin-induced retinitis, the blood-retina barrier at the level of the Bruch's membrane/pigment epithelium appears to be highly resistant to cytotoxic cells. The present observations are in agreement with the concept that the cellular immune response plays a major role in the pathogenesis of (rhod)opsin-induced retinitis.

Phenotypic expression in mucopolysaccharidosis VII

beta-glucuronidase deficiency is an extremely rare disorder which is known to have a considerable phenotypic variation. A survey of the clinical findings in 19 previously reported patients with mucopolysaccharidosis VII is presented together with the results of clinical and biochemical studies in two further patients. Because a similar clinical picture is present in a heterozygotic sister it is doubted whether all signs and symptoms can be attributed to the beta-glucuronidase deficiency. The probability of a concomitant disorder is discussed. Diagnosis was made both by demonstration of the deficiency in plasma and leucocytes, and by means of hair root analysis. The phenotypic variation and the fact that increased levels of glycosaminoglycans were not found in the urine of the two patients lead to the suggestion that in certain cases a correct diagnosis may be missed if the beta-glucuronidase activity in plasma and leucocytes is not determined and only routine urine investigation is performed as a screening for a mucopolysaccharidosis. Hair root analysis may be a useful method to measure the beta-glucuronidase activity.

Early infantile form of neuronal ceroid lipofuscinosis. Four Dutch cases and review of the literature

In this paper four Dutch cases of early infantile neuronal ceroid lipofuscinosis (NCL) are described, all being boys. NCL is a group of diseases morphologically characterized by accumulation of autofluorescent ceroid lipofuscin-like pigment. Psychomotor deterioration, impairment of vision, and epileptic manifestations are the major clinical features. Onset in early infantile age is rare. We reviewed 71 cases reported in the literature, and compared the symptoms and signs with the findings in our patients. Psychomotor deterioration, visual impairment and myoclonic jerks are often observed early in the disease. Eventually, every patient shows psychomotor deterioration. The outcome is always lethal, usually within a few years. Special attention is paid to diagnostic procedures.

Acute generalized microvascular injury by activated complement and hypoxia: the basis of the adult respiratory distress syndrome and multiple organ failure?

It has been suggested that generalized endothelial damage and permeability changes, induced by prolonged activation of the complement system and ensuing release of lysosomal enzymes, prostaglandins and toxic oxygen products, underlie the genesis of the Adult Respiratory Distress Syndrome (ARDS) and Multiple Organ Failure (MOF). The effects in New Zealand white rabbits were investigated of a 4 h infusion of activated complement and its combination with a short hypoxic episode on respiratory function, leukocyte count, platelet count and morphology of the lungs, heart, liver, kidney and spleen. Prolonged activation of the complement system induced hyperventilation with respiratory alkalosis and hypocapnia, depletion of granulocytes (PMN), and a variable accumulation PMN in the capillaries of all organs examined, in combination with interstitial, and, in the liver, cellular oedema. Electron microscopy of the lungs revealed degranulation of PMN, endothelial swelling and widening of the alveolar septa. The combination of hypoxia and systemic complement activation appeared to aggravate this microvascular injury with the occurrence of protein rich alveolar oedema and haemorrhage in the lungs and accumulation of PMN debris containing macrophages in the spleen. The alterations in respiratory function and pulmonary morphology in these rabbits, imitate the clinical and morphological characteristics of the early phase of ARDS. The inflammatory reaction, found in all other organs examined, might represent the early phase of MOF. If so, ARDS and MOF -- clinically closely interconnected syndromes -- might be interpreted as manifestations of the same syndrome and as the clinical expression of an uncontrolled whole body inflammation.

Ultrastructural study of the vacuoles in the peripheral lymphocytes in juvenile amaurotic idiocy. Juvenile form of generalized ceroid lipofuscinosis

Lymphocytes of the peripheral blood of 31 patients with juvenile amaurotic idiocy (juvenile form of ceroid lipofuscinosis) were examined with the electron microscope. In all cases, intracytoplasmic clear vacuoles were present, containing round hollow, fingerprint and highly electron dense structures. The combination of these structures, not necessarily in one and the same vacuole, was considered to be highly indicative for the diagnosis of juvenile amaurotic idiocy. In addition to these three structures, parallel tubular inclusion bodies, rectilinear profiles and rod-shaped structures were found but in a number of the cases. The parallel tubular inclusion bodies were not regarded as having any diagnostic significance.

Ultrastructural study of so-called curvilinear bodies and fingerprint structures in lymphocytes in late-infantile amaurotic idiocy

Peripheral lymphocytes of 6 patients with late-infantile amaurotic idiocy were examined with the electron microscope for the occurrence of curvilinear bodies and fingerprint structures. In 3 of the patients predominantly curvilinear bodies were found; in 1 case they contained some fingerprint profiles. In the remaining 3 patients curvilinear bodies were relatively scarce, whereas fingerprint structures prevailed. Moreover, pleomorphic bodies with rectilinear profiles and parallel tubular inclusion bodies were present. No lymphocytes with vacuoles were observed in any of the patients. The sural nerve biopsies of all patients revealed curvilinear bodies. This tissue consequently may be considered to give more reliable information in comparison with the lymphocyte. The likelihood of transition of one type inclusion body into another, the specificity of the curvilinear body and, to our mind, the rigid classification of the amaurotic idiocy into a curvilinear and a fingerprint type, are discussed.