You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
moreover , secondary syphilis should be considered in the differential diagnosis of any dermatosis which is atypical .
we are reporting a case of secondary syphilis , without any history of a primary lesion , that resembled borderline lepromatous ( bl ) leprosy , and in whom the diagnosis was considered on clinical grounds .
a 57 year old middle class male patient presented with asymptomatic , generalized , annular plaques present for 2 months , and without constitutional symptoms .
the plaques were situated on the front and back of trunk [ figure 1 ] , on the upper extremities and thighs , and on the face , with confluent nodules on the forehead .
the larger plaques were 4 - 5 cm in size , and had succulent papulonodules at the margin [ figure 1 , site of biopsy 1 ] .
other plaques had scaly margins , which were rolled out [ figure 1 ] . on the right forearm there
were eroded , annular plaques , with sharply raised overhanging , and scaly margins [ figure 2 ] .
however , on noting that the plaques showed increased sensitivity to pain ( buschke - ollendorf sign ) , secondary syphilis was also considered . moreover , a generalized and epitrochlear lymphadenopathy was also noted , but there were no mucous patches or condyloma lata .
the plaque with a scaly margin is seen on the left scapular area ( biopsy 2 ) the eroded , annular plaques with scaly margins , on the right forearm , before treatment subsequent investigations confirmed the diagnosis of secondary syphilis , as his rapid plasma reagin ( rpr ) test was reactive in 1:128 dilution , his skin smears were negative for lepra bacilli , and his treponema pallidum haemagglutination test was also positive . on direct questioning ,
he also had concomitant hiv infection by the elisa test , and his cd4 count was 269 cells / cmm .
his chest x - ray was normal , and his eye , cardiovascular , and neurological examination did not reveal any abnormality .
his cerebrospinal fluid ( csf ) examination revealed asymptomatic neurosyphilis , with 10 cells / cmm and 50 mg protein / dl , but with a negative csf venereal disease research laboratory ( vdrl ) test .
his skin biopsy performed from two different plaques showed essentially similar features , with the presence of a florid subepidermal granulomatous infiltrate without a free grenz zone , in biopsy 2 . a few langhans and multinucleate giant cells
were also seen , apart from a periappendageal and perineural granulomatous infiltrate rich in plasma cells [ figure 3 , biopsy 1 ] that was breaking up the arrectores pilorum muscle .
in addition , endothelial swelling , with luminal narrowing , and a perivascular infiltrate of lymphocytes and plasma cells was also present .
a periappendageal and perineural infiltrate ( h and e 200 , biopsy 1 ) the patient received three weekly injections of 2.4 million units of intramuscular benzathine penicillin , along with 2 g of daily intravenous ceftriaxone for 15 days .
he did not develop any fever after any of his injections ( negative jarisch - herxheimer reaction ) .
the plaques on the back had flattened 50% within one week of the penicillin injection [ figure 4 ] and the eroded plaques on the forearm had regressed 70% by then . within 20 days , the plaques had almost totally flattened , and 1 months later , only hyperpigmented macules were remaining . after 4 months his repeat rpr had fallen to 1:64 dilution , and his cd4 count had risen to 547 cells / cmm . when last seen one year later , his rpr had further fallen to 1:16 dilution , and there was no recurrence of his skin lesions .
hence , it is suggested that an rpr / vdrl test should be routinely performed in any atypical dermatosis . in our patient
, there was both a clinical and a histological resemblance to leprosy , as well as atypical features .
however , on careful evaluation , a diagnosis of granulomatous secondary syphilis could have been considered , as there were numerous plasma cells , associated with changes in the blood vessels .
there have been similar reports of secondary syphilis resembling bl or ll leprosy , with , . and without associated hiv .
syphilis , when associated with hiv , could be more severe and unusual , with an increased risk of neurological involvement , hastening of the late stage , and treatment failure . hence , treatment as for late syphilis has been advocated in cases of secondary syphilis , with hiv , along with a mandatory csf test
. we treated his asymptomatic neurosyphilis with the alternative recommended dose of ceftriaxone , . and also decided to complete the course of benzathine penicillin , as it had already been started .
syphilis facilitates the transmission of hiv , by increasing the viral load , and reduces the cd4 count , which increases after the syphilis is successfully treated . in conclusion
, it may be stated that this case has demonstrated the primacy of the time - tested method of a thorough clinical examination and history , followed by the relevant and interpretative investigations , and a good , clinico - pathological correlation for making the correct diagnosis in any unusual dermatosis .
we are reporting an unusual case of secondary syphilis , in a homosexual male patient , which resembled borderline lepromatous leprosy , and in whom the diagnosis was considered on clinical grounds . 
 the patient also had concomitant hiv infection , with asymptomatic neurosyphilis . 
 his rapid plasma reagin test was reactive in 1:128 dilution . 
 he improved with three standard , weekly injections of benzathine penicillin , along with 2 g of intravenous ceftriaxone daily for 15 days . 
 this case is being reported to highlight the need for a high index of suspicion in diagnosing unusual cases of secondary syphilis , especially in those with concomitant hiv infection .