Alveolar capillary basement membrane lesions in Goodpasture's syndrome and idiopathic pulmonary hemosiderosis

Clinical features and risk factors for recurrence of idiopathic pulmonary hemosiderosis in children

BACKGROUND

This study aims to review the clinical characteristics, therapeutic response and outcome of idiopathic pulmonary hemosiderosis (IPH), and discover the risk factors for recurrence in children with IPH, which will be helpful for the early diagnosis and reasonable treatment of this disease.

METHODS

Children with a diagnosis of IPH were enrolled in the study. Clinical data of the children were collected and analysed.

RESULTS

A total of 32 patients with regular follow-up after diagnosis were included in this study. Anaemia, cough and haemoptysis constituted the most common initial symptoms of the disease, and the incidences were 90.6%, 75% and 56.2%, respectively. The mean gap between the onset of symptoms and diagnosis was 5 (0.25-36) months. Most of the children experienced remission (complete and partial remission) over the course of 6 months of treatment, but 19 of the children experienced relapse. The causes of disease recurrence included respiratory tract infection (37.5%), corticosteroid (CS) reduction (18.8%), and irregular medication (6.3%). Interestingly, we found that children with history of allergy (HR 4.255, 1.107-16.356) tended to experience disease recurrence (p = 0.01).

CONCLUSIONS

Cough and anaemia are the most common symptoms in children with IPH. The recurrence rate of this disease is high, and respiratory tract infection is the most common cause of its recurrence. High-dose CS impluse therapy cannot reduce the recurrence rate of the disease. Allergic history was an import factor associated with disease recurrence.

TRIAL REGISTRATION

This study is a retrospective and observational study, which does not involve human specimens or clinical intervention. Therefore, clinical trial registration is not required, and there is no clinical trial number. However, the study was approved by the Institutional Review Board/Ethics Committee affiliated with West China Second University Hospital, Sichuan University (Ethics review number 2022074).

Adult patients with idiopathic pulmonary hemosiderosis: a comprehensive review of the literature

Idiopathic pulmonary hemosiderosis (IPH) is a rare disease without a known incidence or prevalence in adults. Our knowledge of this entity is limited as there is no prospective or retrospective study with a reasonable number of patients. The objective is to describe the demographics, clinical manifestations, diagnosis, treatment, and prognosis of adult patients with IPH. The Medline and Embase databases were searched from inception to 2021 with appropriate search formulas to identify relevant articles following strict inclusion and exclusion criteria. Statistical analyses were performed for the entire cohort and prespecified subgroups. A total of 84 patients were identified. The majority of patients were males 54/84 (64.3%). The median age was 27 years. The manifesting symptoms were present in the following frequencies: anemia 76/83 (91.6%), dyspnea 71/83 (85.5%), hemoptysis 70/84 (83.3%), cough 22/84 (26.2%), and chest pain 9/84 (10.7%). The classic triad was present in 61/84 (79%) patients. The mean hemoglobin during the initial presentation was 8.4 gm/dL. A total of 16/57 (19.5%) tested positive for autoantibodies. The median delay in the diagnosis of IPH was 1.02 years. Immunosuppressive therapy was prescribed in 49/79 (62%) patients, and recurrence occurred in more than half of the patients 36/66 (54.5%). A total of 63/79 (79.7%) patients were alive during the final follow-up. IPH is more common in young adults with a male predominance. A high index of suspicion is necessary to attain an early diagnosis and possibly reduce the short-term mortality of nearly 20% and long-term complications.

The Spectrum of Autoantibodies in Adult Patients With Idiopathic Pulmonary Hemosiderosis: A Brief Review of the Literature

While autoimmune antibodies or autoantibodies have been reported sporadically in adult patients with idiopathic pulmonary hemosiderosis (IPH), their true prevalence is unknown. The question as to whether any difference exists between antibody-positive and negative patients has not been explored. The primary objective of this paper was to assess the spectrum of autoantibody testing and its positivity rate. The other objectives included a comparative analysis of demographics, symptom onset, clinical manifestations, and differences in clinical outcomes between antibody-positive (cohort A) and negative (cohort B) patients. To that end, we conducted a retrospective review of the relevant published literature. Multiple databases were searched to retrieve studies published between 1990 and 2022.

A total of 35 studies, involving 38 patients, were identified. Five of these patients had a positive autoantibody. Patients in cohort A were older and more likely to be male. The frequencies of testing for these antibodies were as follows: antineutrophil cytoplasmic antibody (ANCA): 37/38 (97.4%), antinuclear antibody (ANA): 31/38 (81.6%), and anti-glomerular basement membrane antibody (anti-GBM): 30/38 (78.9%); 5/38 (13.2%) patients tested positive for an autoantibody, and two of these patients were positive for ANA, two for antithyroid antibody, and one patient tested positive for ANCA, rheumatoid factor (RF), and granulocyte monocyte-colony stimulating factor (GM-CSF) antibody. There was no difference between the cohorts regarding their clinical presentations, recurrence risks, and survival.

The occurrence of autoantibodies is uncommon in adult IPH patients. This is in contrast with the pediatric IPH patient population, where the prevalence is much higher (26.4% vs. 13.2%), and the antibodies are more diverse. Unlike pediatric patients, adult patients with autoantibodies do not necessarily have worse outcomes.

Proposed Pathogenesis of Diffuse Alveolar Hemorrhage in Idiopathic Pulmonary Hemosiderosis

Idiopathic pulmonary hemosiderosis (IPH) is a rare disease that causes diffuse alveolar hemorrhage (DAH). The latest data suggests an immunologic origin of IPH, and a new name, immune mediated pulmonary hemosiderosis (ImPH), has been proposed. However, the exact immunologic mechanism has remained elusive for nearly eight decades despite extensive research, including detailed histopathologic analysis. Although several hypotheses have been proposed to describe the pathobiology of IPH, none of them explain the clinical and histopathologic findings conclusively. In this manuscript, we have presented a new hypothesis for the pathogenesis of DAH in IPH. We hypothesize that DAH in IPH is not immunocomplex mediated but due to histamine, eosinophilic cationic protein (ECP), and possibly vascular endothelial growth factor (VEGF). These bioactive proteins induce endothelial and alveolar epithelial damage, leading to the peri-capillary and intraalveolar escape of RBCs. The deformability of the RBC likely also plays a role. The supranormal secretion of histamine, ECP and VEGF occurs in genetically predisposed individuals with an aberrant immunologic response. The histamine is released from the basophils and possibly the mast cells in response to cytokines secreted by activated lymphocytes. The lymphocyte activation occurs after exposure to a known (gluten) or unknown antigen. The same lymphocyte-derived cytokines also induce eosinophilic degranulation of ECP and VEGF in the pulmonary circulation. We believe that our hypothesis unifies the observed clinical variabilities and histopathologic findings in IPH, and we hope that would promote future research in the field of IPH.

Comparative Analysis of Adult Patients With Idiopathic Pulmonary Hemosiderosis and Lane-Hamilton Syndrome: A Systematic Review of the Literature in the Period 1971-2022

Idiopathic pulmonary hemosiderosis (IPH) causes diffuse alveolar hemorrhage (DAH) by a yet unknown mechanism. The coexistence of IPH and celiac disease (CD), also known as Lane-Hamilton syndrome (LHS), has been reported in both pediatric and adult patients. The objective of this study was to compare demographics, clinical and radiologic findings, treatment, and outcomes between adult patients with IPH and LHS.

This is a systematic review of the literature. Multiple databases were searched using appropriate formulas to identify relevant articles. A total of 60 studies reporting 65 patients were included in the review. Forty-nine of these patients had IPH and 16 had LHS. The prevalence of anti-CD antibodies among tested patients was 13/22 (59%). The symptom onset and diagnosis of IPH occurred earlier in patients with LHS. The median delay in diagnosis was the same between the two groups (52 weeks). The classic triad was more likely to be present in patients with LHS. Only 20% of patients in the LHS cohort had any significant gastrointestinal (GI) symptoms at the time of IPH diagnosis. A gluten-free diet alone was effective in the majority of patients. Fewer patients in the LHS cohort received systemic corticosteroid than the IPH cohort. The recurrence and mortality in patients with LHS appear to be less than in the IPH cohort. The prevalence of CD is 25% in adult patients with IPH. Patients with LHS may have a milder course than patients without CD. Serologic testing for CD should be performed in all patients diagnosed with IPH.

Differentiation of idiopathic pulmonary hemosiderosis from rheumatologic and autoimmune diseases causing diffuse alveolar hemorrhage: establishing a diagnostic approach

This narrative review provides an overview of diffuse alveolar hemorrhage (DAH) associated with rheumatologic and autoimmune diseases and their differentiation from idiopathic pulmonary hemosiderosis (IPH). Relevant immunologic diseases associated with DAH are discussed, and a diagnostic flowchart is proposed to establish a "definitive" diagnosis of IPH within the spectrum of DAH. IPH is a rare cause of recurrent DAH both in children and adults. In adults, a definitive diagnosis of IPH requires a lung biopsy and histopathologic examination demonstrating intraalveolar hemorrhage, hemosiderin-laden macrophages, and a variable degree of fibrosis in the absence of both capillaritis and cellular inflammation. The presence of small vessel vasculitis points towards immunologic, well-differentiated, or sometimes undifferentiated rheumatologic diseases. However, it is essential to recognize that many rheumatologic diseases may in the initial phase present with DAH without any evidence of capillaritis, thus mimicking IPH. Although not definitely established, it is likely that immunologic processes are involved in IPH, and we, therefore, suggest the consideration of a more suitable term for the disease, e.g., "Immune-mediated Pulmonary Hemosiderosis" to acknowledge the aberrancy in the immune parameters and a positive response to immunosuppressive therapy.

Idiopathic pulmonary hemosiderosis: A state of the art review

Idiopathic pulmonary hemosiderosis (IPH) is an uncommon cause of diffuse alveolar hemorrhage (DAH). Patients with IPH usually present with hemoptysis, and the diagnosis is often delayed by years. Patients often present with intermittent episodes of hemoptysis interspersed between periods of relative normalcy. However, massive hemorrhage resulting in acute respiratory failure and non-remitting hemoptysis have also been described. The classic triad includes hemoptysis, radiologic lung infiltrate, and iron deficiency anemia. Several hypotheses regarding the pathogenesis of IPH have been proposed. These risk factors include an autoimmune, allergic or genetic predisposition, and possible environmental exposure. Since IPH appears to be responsive to corticosteroids, the autoimmune hypothesis is considered to play a crucial role. A diagnosis of IPH requires exclusion of other etiologies of DAH, including infection, medications, toxic inhalation, vasculitis, and anti-glomerular basement membrane disease, among others. Histologically, IPH is characterized by the presence of hemosiderin-laden macrophages in the alveolar space without any evidence of vasculitis or immunocomplex deposition. Corticosteroid therapy represents the primary modality of treatment. Other immunosuppressive medications have also been used with varying success, especially in the setting of steroid-refractory disease. The prognosis of IPH in adults is somewhat better compared to the pediatric population. The severity of the initial presentation does not predict future outcomes. Which risk factors and patient characteristics are associated with a poor outcome are also unknown. More research is necessary to elucidate the pathophysiology and appropriate treatment.

Hemoptysis due to breath-hold diving following chemotherapy and lung irradiation

Breath-hold diving, also known as free-diving, describes the practice of intentional immersion under water without an external supply of oxygen. Pulmonary hemorrhage with hemoptysis has been reported as a complication of immersion and breath-hold diving in young healthy athletes. We report the case of a 60-year-old man with a history of radiation and chemotherapy for breast carcinoma, who developed the abrupt onset of hemoptysis in the setting of swimming and breath-hold diving. A computed tomography (CT) scan of the chest demonstrated an area of ground glass opacification, suggestive of pulmonary hemorrhage, superimposed on a background of reticular opacities within the prior radiation field. A follow-up CT scan of the chest, obtained 2 months after presentation, demonstrated resolution of the ground glass opacification, but persistence of fibrotic features attributable to prior radiation therapy. We postulate that prior irradiation of the chest resulted in lung injury and fibrosis which, in turn, rendered the affected region of the lung susceptible to "stress failure," due to an increase in the transcapillary pressure gradient arising from immersion and breath-hold diving. Patients with a history of lung injury resulting from chest irradiation should be cautioned about pulmonary hemorrhage and hemoptysis as a potential complication of swimming and breath-hold diving.

Alveolar haemorrhage in anti-glomerular basement membrane disease without detectable antibodies by conventional assays

Anti-glomerular basement membrane (anti-GBM) disease represents the spectrum of disease attributable to circulating anti-GBM antibodies. While active anti-GBM disease in the absence of circulating anti-GBM antibodies has been described, it is considered rare with the use of current routinely available assays. We report four subjects with features consistent with active anti-GBM antibody disease without detectable antibodies by routinely available enzyme linked immunosorbent assay (ELISA) and immunoblot techniques. All were smokers who presented with diffuse alveolar haemorrhage, minimal renal involvement, and undetectable anti-GBM antibodies. Seronegative anti-GBM disease with predominant pulmonary involvement may be more common than previously appreciated and should be part of the differential diagnosis for otherwise unexplained diffuse alveolar haemorrhage. Renal biopsy with immunofluorescent studies should be considered in the diagnostic evaluation of such subjects, including those with idiopathic pulmonary haemosiderosis.

Hemoptysis provoked by voluntary diaphragmatic contractions in breath-hold divers

Pulmonary barotrauma of descent (lung squeeze) has been described in breath-hold divers when the lung volume becomes smaller than the residual volume (RV), with the effect of increased ambient pressure. However, the ratio between the total lung capacity and the RV is not the only factor that plays a role in the lung squeeze. Blood shift into the thorax is another important factor. We report three cases of hemoptysis in breath-hold divers who dove for spear fishing in shallower depths than usual. All of the divers performed voluntary diaphragmatic contractions at the beginning of their ascent, while their mouths and noses were closed. We suggest that the negative intrathoracic pressure due to the forced attempt to breathe in with voluntary diaphragmatic contractions contributes to alveolar hemorrhage, since it may damage the pulmonary capillaries.

Long-term outcome of idiopathic pulmonary hemosiderosis in children

We retrospectively analyzed the long-term outcome of idiopathic pulmonary hemosiderosis (IPH) in 15 children. IPH started at a mean age of 5 years, and the mean duration of follow-up was 17.2 years (range, 10-36 yr). Four patients developed immune disorders, 3 cases of rheumatoid polyarthritis or rheumatoid polyarthritis-like diseases and 1 case of celiac disease. Respiratory outcome showed that 3 patients had severe symptoms: 2 patients developed severe pulmonary fibrosis resulting in major chronic respiratory insufficiency, and 1 patient had severe asthma. Twelve patients (80%) had mild or no respiratory problems and were able to lead a normal life. According to chest X-ray and pulmonary function test data, 4 patients had normal chest X-ray and no evidence of restrictive syndrome, 6 patients had an interstitial pattern on chest X-ray and evidence of restrictive pattern, 1 patient had an interstitial pattern but normal lung function, and 1 patient had a normal chest X-ray but evidence of mixed obstructive and restrictive pattern. Our results show that long-term survival is possible in patients with IPH. Factors of poor prognosis seem to be the presence of antineutrophil cytoplasm antibodies (ANCA) or other autoantibodies. No other clinical or biological predictive factors for prolonged survival were found.

Idiopathic pulmonary haemosiderosis. Epidemiology, pathogenic aspects and diagnosis

Idiopathic pulmonary haemosiderosis (IPH) is a rare clinical entity characterized by recurrent episodes of diffuse alveolar haemorrhage, often presenting with haemoptysis. Many patients have iron deficiency anaemia due to deposition of haemosiderin iron in the alveoli, and eventually develop moderate pulmonary fibrosis. Typically, intensive search for an aetiology ends up negative. There is no evidence of pulmonary vasculitis or capillaritis. The aetiology is obscure, but may be an immunological or toxic mechanism causing a defect in the basement membrane of the pulmonary capillary. IPH affects both children and adults. During an acute episode, a chest X-ray demonstrates bilateral, alveolar infiltrates. Sputum examination discloses haemosiderin-laden alveolar macrophages. Diagnosis is established by lung biopsy (fiber-optic or thoracoscopic), showing large numbers of haemosiderin-laden macrophages in the alveoli and without evidence of capillaritis or deposition of immunoglobulins. Corticosteroids and/or immunosuppressive drugs may be effective during an acute bleeding episode, and may in some patients improve symptoms and prognosis on the long-term, but the response to treatment displays great interindividual variation.

p50-NF-kappaB complexes partially compensate for the absence of RelB: severely increased pathology in p50(-/-)relB(-/-) double-knockout mice

RelB-deficient mice (relB(-/-)) have a complex phenotype including multiorgan inflammation and hematopoietic abnormalities. To examine whether other NF-kappaB/Rel family members are required for the development of this phenotype or have a compensatory role, we have initiated a program to generate double-mutant mice that are deficient in more than one family member. Here we report the phenotypic changes in relB(-/-) mice that also lack the p50 subunit of NF-kappaB (p50(-/-)). The inflammatory phenotype of p50(-/-)relB(-/-) double-mutant mice was markedly increased in both severity and extent of organ involvement, leading to premature death within three to four weeks after birth. Double-knockout mice also had strongly increased myeloid hyperplasia and thymic atrophy. Moreover, B cell development was impaired and, in contrast to relB(-/-) single knockouts, B cells were absent from inflammatory infiltrates. Both p50(-/-) and heterozygous relB(-/+) animals are disease-free. In the absence of the p50, however, relB(-/+) mice (p50(-/-)relB(-/+)) had a mild inflammatory phenotype and moderate myeloid hyperplasia. Neither elevated mRNA levels of other family members, nor increased kappaB-binding activities of NF-kappaB/Rel complexes could be detected in single- or double-mutant mice compared to control animals. These results indicate that the lack of RelB is, in part, compensated by other p50-containing complexes and that the "classical" p50-RelA-NF-kappaB activity is not required for the development of the inflammatory phenotype.

Epitope mapping of homologous and cross-reactive antigens by monoclonal antibodies to streptococcal cell membrane (mAb to SCM)

An approach to epitope mapping of a series of anti-streptococcal cell membrane (SCM) mAbs is described. Evaluations by enzyme-linked immunosorbent assay (ELISA) of one control mAb HB-35 and 13 different anti-SCM mAbs were made on homologous SCM antigen and human basement membrane antigens isolated from glomeruli (GBM) and lung (LBM). These anti-SCM mAbs were previously shown to be cross-reactive in a variety of systems with both GBM and LBM. The binding capacities were measured for all 14 mAbs on ELISA plates sensitized with SCM antigen or the cross-reactive GBM or LBM antigens, at 5 micrograms/ml or approximately 20 pM/well. From the 50% binding capacity dilution the pM of mAb bound/pM antigen-well was calculated which translated into an estimate of the ratio-number of epitopes bound. Observations with the homologous and cross-reactive antigens showed multiple reactive epitope ratios to eight mAbs whereas the other five yielded a ratio value of one or two on the tested antigens. Plates blocked with a specific dilution of one mAb evaluated the binding by a second mAb providing both binding and specificity data. One mAb (I-F-3) blocked all the other anti-SCM mAbs on all three antigen plates. An additive effect was noted by three mAbs, I-G-8, II-C-4 and II-D-8 with most of the other mAbs. The order of placement, however, made distinctive differences; II-F-4 showed an additive or enhancement effect on I-B-5 but no reciprocal effect was seen. A similar effect was made with I-G-8 and II-C-4 or I-F-7. Possible interpretations are that each mAb is binding different epitopes each fully exposed, and the order of placement of the mAbs makes no difference. Where an enhanced effect was observed it is suggested that the binding of the first mAb changed the conformation of the antigen, thereby opening and exposing additional epitope(s) to the second antibody. Or, in contrast, where the second mAb was blocked by the first, a fixing of the protein conformation is suggested thereby occluding the other epitope, as seen with I-F-3 and II-C-4. These epitope mapping procedures confirmed that all 13 anti-SCM mAbs were binding at different epitopes. The nature of basement membrane collagens and how this relates to post-streptococcal sequelae will be discussed.

Antineutrophil cytoplasmic antibodies (ANCA) in idiopathic pulmonary hemosiderosis

Four children were diagnosed with idiopathic pulmonary hemosiderosis (IPH), over a period of 4 years. Retrospectively, antineurtrophil cytoplasmic antibodies (ANCA) were studied by indirect immunofluorescence (IIF) and ELISA in 18 sera from these patients, stored at -20 degrees C. ANCA-positive sera, from 1/20 to 1/1, 200 dilution, were found in 3/4 of the patients, by IIF. The patient with the highest titre of ANCA died 3 months later during an acute crisis, the other two patients need a minimal dose of steroids. In one case only, a patient who is still without treatment, had no ANCA. The antibodies anti-myeloperoxidase and anti-proteinase-3 were negative or at border line levels. Rheumatoid factor, antinuclear (Hep-2), anti-endomysial, anti-reticulin and antibasement membrane antibodies were negative in all sera. The surviving patients were followed-up for more than 10 years with no systemic or renal disease appearances. The presence of serum ANCA may help to classify children with pulmonary haemorrhage and may have a prognostic value.

Circulating immune complexes with pulmonary hemorrhage during pregnancy in idiopathic pulmonary hemosiderosis

Circulating immune complexes occurred during pulmonary hemorrhage in a pregnant patient with idiopathic pulmonary hemosiderosis, an association not previously reported. The patient required mechanical ventilation, but recovered; after a prolonged hospitalization, she was delivered of a healthy infant without further complications.

Stress failure of pulmonary capillaries: role in lung and heart disease

Pulmonary capillaries have extremely thin walls to allow rapid exchange of respiratory gases across them. Recently it has been shown that the wall stresses become very large when the capillary pressure is raised, and in anaesthetised rabbits, ultrastructural damage to the walls is seen at pressures of 40 mm Hg and above. The changes include breaks in the capillary endothelial layer, alveolar epithelial layer, and sometimes all layers of the wall. The strength of the thin part of the capillary wall can be attributed to the type IV collagen in the extracellular matrix. Stress failure of pulmonary capillaries results in a high-permeability form of oedema, or even frank haemorrhage, and is apparently the mechanism of neurogenic pulmonary oedema and high-altitude pulmonary oedema. It also explains the exercise-induced pulmonary haemorrhage that occurs in all racehorses. Several features of mitral stenosis are consistent with stress failure. Overinflation of the lung also leads to stress failure, a common cause of increased capillary permeability in the intensive care environment. Stress failure also occurs if the type IV collagen of the capillary wall is weakened by autoantibodies as in Goodpasture's syndrome. Neutrophil elastase degrades type IV collagen and this may be the starting point of the breakdown of alveolar walls that is characteristic of emphysema. Stress failure of pulmonary capillaries is a hitherto overlooked and potentially important factor in lung and heart disease.

Long-term clinical follow-up of adult idiopathic pulmonary hemosiderosis and celiac disease

A 22-year-old man with a history of repeated whole blood transfusions since the age of 7, was admitted to the hospital for dyspnea and blood-stained sputum. A complete blood cell count, a test for reticulin antibodies, an x-ray film of the chest, a transbronchial biopsy and a biopsy of the small bowel were performed and the results confirmed the diagnosis of IPH, associated with CD. The patient has been asymptomatic for four years on a gluten-free diet. In cases of IPH, it may be important to investigate the coexistence of CD because treatment of the latter could lead to a better prognosis.

Hybridomas to specific streptococcal antigen induce tissue pathology in vivo; autoimmune mechanisms for post-streptococcal sequelae

A gross examination of organs from approximately 100 mice which were producing ascites fluids toward a series of streptococcal reactive monoclonal hybridomas showed, in some animals, what appeared to be autoimmune-like findings. A pattern of major lung pathology was associated with specific clones. These specific hybridomas led to the development of an experimental autoimmune animal model mimicking a Goodpasture's syndrome. Tissue injury was induced in mice, on a dose dependent basis, by the injection of monoclonal antibody generated against streptococcal cell membrane (SCM) antigens. A more severe onset of the pathology, also on a dose dependent bases, was induced by placement of the anti-SCM mAb secreting hybridoma cells into the peritoneal cavity of the host. Severity of observed lesions was dependent upon the number of cells injected (10(5), 5 x 10(5), 10(6) or 10(7], as well as the animals' sex. Severe and total hemorrhagic lungs were seen in animals challenged with 1 x 10(6) hybridomas cells when sacrificed on the tenth day. In all cases the lesions were greater in the female litter mate than the male. Gross and histologic observations were confirmed by lung/body weight ratios. Pulmonary hemorrhage ranged from slight, when mAb was injected at a low dose of 24 micrograms/g, to severe when 96 micrograms/g was injected. Reported findings were based on the review of approximately 300 mice. Immunochemical evaluations and ELISAs confirmed the ability of these anti-SCM mAb to react with glomerular basement membrane (GBM) antigens as well as lung basement membrane (LBM). Mitogenic experiments indicated that the parent immunogen (SCM) used to generate immunocytes was non-stimulatory to lymphocytes.

Surgical pathology of the lung in anti-basement membrane antibody-associated Goodpasture's syndrome

We report the findings of lung biopsies from five patients with anti-basement membrane antibody-associated Goodpasture's syndrome (ABMA-GS). In four patients, pulmonary capillaritis with hemorrhage was found on lung biopsy, confirming that pulmonary capillaritis can be found in ABMA-GS. Although alveolar hemorrhage was the dominant pathologic finding in four of our five patients, all five patients had evidence of injury at the level of the alveolar wall, manifested by hyaline membranes and widening of alveolar walls by edematous connective tissue. In one of our patients, alveolar hemorrhage was only focal, and diffuse alveolar damage was the dominant pathologic finding. This pattern of lung disease has not been previously described in ABMA-GS.

Fine structural changes in idiopathic pulmonary haemosiderosis

Lung biopsies from four children and two adults with idiopathic pulmonary haemosiderosis have been examined by transmission electron microscopy. No qualitative differences were identified between the children and the adults but the changes were more severe in the children. In each case the major damage involved the capillary endothelium and its basement membrane. Capillary endothelial swelling was very noticeable and in one case the endothelium was attenuated but gaps between endothelial cells were very difficult to find. Capillary narrowing and platelet aggregation were common. The capillary endothelial basement membrane showed focal thickening, particularly on the thick side of the air/blood barrier, but no electron dense deposits were identified. Degenerative changes in the alveolar epithelium were not so marked as those in the capillary endothelium and the epithelial basement membrane was normal except for haemosiderin deposition. Haemosiderin was also noted on elastin and within intra-alveolar macrophages. Other secondary changes included mild interstitial oedema and fibrosis. These findings indicate that the major site of damage is the alveolar capillary, but provide no evidence of the cause of the disease.

Idiopathic pulmonary haemosiderosis. The peri-operative anaesthetic management of a patient for open lung biopsy

The peri-operative anaesthetic management and hazards of a patient with idiopathic pulmonary haemosiderosis are described in association with the relevant known clinical and pathological data.

Idiopathic pulmonary hemorrhage. Ultrastructural and mineralogic study

A nine-year-old girl was hospitalized because of hypoxemia and anemia. Antibasement-membrane antibodies were present in the serum, but there was no renal involvement suggestive of Goodpasture's glomerulonephritis. Biopsy of the lung showed pulmonary hemosiderosis. In ultrastructural analysis, no lesion of the alveolar basement membrane or capillary endothelial cells was found; however, ferritin-looking deposits were present on alveolar basement membranes and the elastic lamina of arterioles and venules. Mineralogic studies showed these deposits to be made of iron and calcium (this latter element was probably precipitated on altered basement membranes or elastic lamina). Hemosiderin inclusions in the macrophages contained iron but no detectable calcium.

The chest X-ray in antiglomerular basement membrane antibody disease (Goodpasture's syndrome)

The chest radiographs of 25 patients with proven antiglomerular basement membrane antibody disease (Goodpasture's syndrome) were analysed. All except two of the patients had pulmonary haemorrhage at some stage of their disease. Altogether there were 39 episodes of pulmonary haemorrhage, 25 being relapses. During seven episodes the chest radiograph was normal. Relapses of pulmonary haemorrhage never occurred in isolation but were usually associated with infection (not necessarily a chest infection) or occasionally fluid overload. Conversely fluid overload or infection were always associated with pulmonary haemorrhage provided there were high or rising titres of circulating antibodies at the time. Therefore in a patient with antiglomerular basement membrane antibody disease, the presence of shadowing in the lung fields on the chest radiograph almost invariably means the patient has pulmonary haemorrhage whether or not pulmonary oedema or a chest infection are present. Limitation of shadowing by a fissure, loss of major portions of the diaphragmatic or cardiac silhouette, involvement of the lung apex or costophrenic angles suggest an underlying chest infection. Septal lines suggest fluid overload. Pleural effusions are seen with chest infections and fluid overload. The carbon monoxide uptake (KCO) was invariably high in the presence of pulmonary haemorrhage even if the chest radiograph was normal. A combined use of KCO and chest radiographs is the best method of monitoring lung disease in these patients.

Idiopathic pulmonary haemosiderosis: report of two cases and review of the literature

Idiopathic pulmonary haemosiderosis (IPH) is a rare disorder affecting mainly children and adolescents, and is usually fatal. However, there is increasing evidence that the aetiology of this condition is immunological, and that immunosuppressives may prolong remission. Two cases are reported, one of which has the atypical feature of a malabsorption syndrome. This has not been previously reported. The literature is reviewed and current ideas on the postulated immunological basis to IPH are discussed.

Goodpasture's syndrome with normal renal function

Two male patients with Goodpasture's syndrome manifesting as severe pulmonary hemorrhage with minimal renal abnormalities are described. Both patients had microscopic hematuria with normal renal function, and one had transient proteinuria. Renal glomerular histology was normal and electron microscopic findings revealed no electron-dense deposits, but immunofluorescence of immunoglobulin G (IgG) was positive in a linear fashion along glomerular capillary basement membranes in both patients. Pulmonary hemorrhage was arrested following prednisone therapy, and both patients have normal pulmonary and renal function at five and 13 months of follow-up. The literature on patients with Goodpasture's syndrome, pulmonary hemorrhage and normal renal function with minimal proteinuria is reviewed. It is suggested that a subset of patients with Goodpasture's syndrome have pulmonary hemorrhage as their major manifestation. Since prednisone seems to have an apparent beneficial effect on pulmonary hemorrhage, and relatively good prognosis, this diagnosis should be considered in patients with idiopathic pulmonary hemorrhage.

Goodpasture's syndrome: an analysis of 29 cases

The pathologic features of 29 cases of Goodpasture's syndrome occurring during a 13-yr period in Auckland have been reviewed and correlated with clinical findings. There were 20 males and nine females in the series; two of the males and three of the females were Maoris. Age at the time of onset of symptoms ranged from 17 to 75 yr, with about 76% of the patients being from 17 to 27 yr of age. Sixteen (55%) of the patients died from less than a week up to about two years following the onset of symptoms, and the remaining 13 are live from 30 weeks to 14 yr after initial presentation. Underlying renal disease varied from mild focal glomerulitis to end-stage glomerulonephritis by light microscopy, but characteristic glomerular changes were seen in all specimens examined by electron and immunofluorescent microscopy. The lungs of 13 of the patients examined at autopsy showed typical abnormalities. The syndrome pursues a notably variable clinical course, affects a considerable proportion of females, occurs over a wide age range, and appears to be disporportionately common among Maoris.

Pulmonary haemorrhage in disseminated cardiac haemangiosarcoma

A male forestry worker presented with chest pain followed by severe continuing haemoptysis and an extensive bilateral nodular pulmonary infiltrate. A needle biopsy of lung demonstrated micronodular deposits of malignant tissue. The patient died from respiratory failure. Necropsy showed a disseminated haemangiosarcoma arising in the right atrium. Haemoglobin and serum iron levels were normal. Electron microscopy of the lung biopsy showed a close relationship between tumour cells and basement membrane and suggested that haemorrhage occurred directly from the tumour nodules. The ultrastructure of alveoli adjacent to tumour deposits was normal. This case provides further indirect evidence that the clinical and histological features of idiopathic pulmonary haemosiderosis cannot be explained by the mere occurrence of alveolar haemorrhage.