Benign Lymphadenopathy Presented in a Malignant Pathway-A Rare Case of Proteinaceous Lymphadenopathy

Citation: Islam MS, Kotoucek P (2018) Benign Lymphadenopathy Presented in a Malignant Pathway A Rare Case of Proteinaceous Lymphadenopathy. Int J Blood Res Disord 5:030. doi.org/10.23937/24695696/1410030 Accepted: June 28, 2018: Published: June 30, 2018 Copyright: © 2018 Islam MS, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Introduction
Lymphadenopathy is a common clinical presentation in haematology outpatient departments.It is a cause of concern for the patient and physician alike even in the absence of symptoms.Proteinaceous lymphadenopathy also known as Hyaline deposition of lymph node is a rare condition and it is often a nonspecific finding.Its incidence increases with age [1,2] and may reduce nodal function.A study has shown two distinct types of lymph node hyalinization-mediastinal-type hyalinisation where onion-peel lesions and associated meshwork areas were often found in the medullary sinus of the thoracic node and pelvic-type hyalinisation-where eosinophilic, glassy and spotty lesions were consistently seen in B lymphocyte areas of the pelvic node [2].This difference seemed to be consistent with a difference in composite collagen fibrils Check for updates mal Lactate Dehydrogenase (LDH) 264 iu/L and C-reactive protein normal.He had a CT scam of the abdomen and pelvis which showed normal intra-abdominal organs, one cystic mass in right inguinal fossa of 5.3 × 3 cm in diameter.There was also bi-lateral inguinal lymphadenopathy with maximum size of 4.5 cm.He also had a cystic swelling of 20 × 12 cm diameter in his left upper thigh/left groin.Subsequently he had a magnetic resonance imaging (MRI) scan of pelvis which confirmed the above finding and also showed urinary bladder diverticula and computerised tomography scan (CT scan) showed large cystic swelling of left thigh was due to subcutaneous oedema (Figure 1).He did not undergo any investigation for his subcutaneous oedema of left upper thigh.However, fortunately his oedema improved with oral furosemide on subsequent out-patient visits.
Multiple large core biopsies were obtained from the largest left inguinal lymph node which showed deposition of eosinophilic hyaline material and the possibility of this eosinophilic hyaline material being amyloid has been excluded by negative Congo red stain (Figure 2).These samples also did not show any metastatic carcinoma or any lymphoma on haematoxylin & eosin (H&E) staining.It also did not show any vascular involvement of lymph nodes or any hyalinisation of vessels of lymph node.Rheumatological blood tests anti-CCP antibodies 1.1 U/ml was within normal range and connective tissue disease (CTD) Screen was also normal at 0.5.His serum immunoglobulin levels were normal; no monoclonal band was detected on electrophoresis.Serum light chain analysis showed slightly raised kappa free light chain 32.84 mg/L (range 3.3-19.4mg/L), normal lambda free light chain 7.65 mg/L (range  5.7-26.3mg/L).Virology screens were all negative.His liver function tests were all normal.Complement levels were not evaluated.Hence no obvious cause for the histological finding of hyaline deposition of lymph node was identified in our patient.Urinary bladder diverticula were thought be an incidental finding in our patient as there was no back flow or any significant pressure was detected on CT scan or MRI scan in this patient.

Discussion
Proteinaceous lymphadenopathy usually associated with rheumatoid arthritis and systemic sclerosis [3,4].It appears that there is a good clinical response in RA-associated proteinaceous lymphadenopathy following successful treatment of arthritis [3,4].It has also been reported in infective condition like HIV or Kikuchi's disease [5].It has also been seen in association with hypergammaglobulinemia [6,7] and post-treatment changes for carcinoma [8].The histopathologist should be familiar with the morphological appearances of this condition, which can be confused with amyloidosis.
Proteinaceous lymphadenopathy of unknown aetiology is an exceedingly rare condition and we could not find any case without underlying cause or association in the literature.Described primarily as a pathologic entity, relatively little is known about its clinical manifestations or its response to therapy.The disease is often referred to and treated as an unusual form of plasma cell dyscrasia or light chain deposition disease [9].Contrary to the notion that this condition is a clonal disorder [9] we found no obvious evidence of clonality in this patient.A Case of Proteinaceous lymphadenopathy was reported in literature [9] where the authors named that as angiocentric sclerosing lymphadenopathy (ASL) with proteinaceous lymphadenopathy with hyper-gammaglobulinemia (PLWH)-a polyclonal Systemic, non-amyloid deposition disorder.However, our patient did show normal immunoglobulin levels and there was no vascular hyaline deposition in vessels in lymph node biopsy.Contrary to that reported case our patient has normal liver function test although we did not check complement level in our patient which was found to be low in that reported case [9].Slightly raised Kappa light chain may suggest autoimmune process and patient has been referred to rheumatology team.
Malignant lymphoma with sclerosis is the most important consideration in the differential diagnosis.Extensive lymph node hyalinisation is particularly common in the inguinal and iliac group of nodes as was seen in our patient [3].Hyalinisation of lymph node can also be seen following inflammatory conditions such as sarcoidosis [10] or tuberculosis which should in mind when evaluating such conditions [11].These changes may result from longstanding non-specific low-grade inflammation [12].Occasionally extensive lymph node hyalinisation may be found with no clue as to its possible aetiology as seen in our case hence we suggest that there is entity of proteinaceous lymphadenopathy of unknown aetiology.This hyaline material may calcify, in time.

Conclusion
Proteinaceous lymphadenopathy which is usually a benign condition that occurs in association rheumatological conditions, infections and hypergammaglobulinemia.Incidence increases with age [1,2].Malignant lymphoma with lymph node sclerosis and amyloid deposition should be considered in differential diagnosis.

Figure 1 :
Figure 1: CT scan showed large swelling due to subcutaneous oedema (above) and MRI pelvis showing urinary Bladder diverticula (below).

Figure 2 :
Figure 2: Thin arrow-H&E stain, thick arrow-negative Congo Red stain.H&E staining showed hyaline deposition of lymph node without any clonal plasma cell (thin arrow) & Negative Congo red stain for amyloid (thick arrow).